- Low-energy collision-induced dissociation mass spectra of protonated p-toluenesulfonamides derived from aliphatic amines
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Collision-induced fragmentation of protonated N-alkyl-p-toluenesulfonamides primarily undergo either an elimination of the amine to form CH 3-(C6H4)-SO2 + cation (m/z 155) or an alkene to form a cation for the protonated p-toluenesulfonamide (m/z 172). To comprehend the fragmentation pathways, several deuterated analogs of N-decyl-p-toluenesulfonamides were prepared and evaluated. Hypothetically, two mechanisms, both of which involve ion-neutral complexes, can be envisaged. In one mechanism, the S-N bond fragments to produce an intermediate [sulfonyl cation/amine] complex, which dissociates to afford the m/z 155 cation (Pathway A). In the other mechanism, the C-N bond dissociates to produce a different intermediate complex. The fragmentation of this [p-toluenesulfonamide/ carbocation] complex eliminates p-toluenesulfonamide and releases the carbocation (Pathway B). Computations carried out by the Hartree-Fock method suggested that the Pathway B is more favorable. However, a peak for the carbocation is observed only when the carbocation formed is relatively stable. For example, the spectrum of N-phenylethyl-p-toluenesulfonamide is dominated by the peak at m/z 105 for the incipient phenylethyl cation, which rapidly isomerizes to the remarkably stable methylbenzyl cation. The peaks for the carbocations are weak or absent in the spectra of most of N-alkyl-p- toluenesulfonamides because alkyl carbocations, such as the decyl cation, rearrange to more stable secondary cations by 1,2-hydride and alkyl shifts. The energy freed is not dissipated, but gets internalized, causing the carbocation to dissociate either by transferring a proton to the sulfonamide or by releasing smaller alkenes to form smaller carbocations. The loss of the positional integrity in this way was proven by deuterium labeling experiments. [Figure not available: see fulltext.]
- Bialecki, Jason B.,Weisbecker, Carl S.,Attygalle, Athula B.
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Read Online
- Highly Selective Hydrogenative Conversion of Nitriles into Tertiary, Secondary, and Primary Amines under Flow Reaction Conditions
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Flow reaction methods have been developed to selectively synthesize tertiary, secondary, and primary amines depending on heterogeneous platinum-group metal species under catalytic hydrogenation conditions using nitriles as starting materials. A 10 % Pd/C-packed catalyst cartridge affords symmetrically substituted tertiary amines in good to excellent yields. A 10 % Rh/C-packed catalyst cartridge enables the divergent synthesis of secondary and primary amines, with either cyclohexane or acetic acid as a solvent, respectively. Reaction parameters, such as the metal catalyst, solvent, and reaction temperature, and continuous-flow conditions, such as flow direction and second support of the catalyst in a catalyst cartridge, are quite important for controlling the reaction between the hydrogenation of nitriles and nucleophilic attack of in situ-generated amines to imine intermediates. A wide variety of aliphatic and aromatic nitriles could be highly selectively transformed into the corresponding tertiary, secondary, and primary amines by simply changing the metal species of the catalyst or flow parameters. Furthermore, the selective continuous-flow methodologies are applied over at least 72 h to afford three different types of amines in 80–99 % yield without decrease in catalytic activities.
- Yamada, Tsuyoshi,Park, Kwihwan,Furugen, Chikara,Jiang, Jing,Shimizu, Eisho,Ito, Naoya,Sajiki, Hironao
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- Direct Enzymatic Synthesis of Fatty Amines from Renewable Triglycerides and Oils
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Fatty amines represent an important class of commodity chemicals which have broad applicability in different industries. The synthesis of fatty amines starts from renewable sources such as vegetable oils or animal fats, but the process has multiple drawbacks that compromise the overall effectiveness and efficiency of the synthesis. Herein, we report a proof-of-concept biocatalytic alternative towards the synthesis of primary fatty amines from renewable triglycerides and oils. By coupling a lipase with a carboxylic acid reductase (CAR) and a transaminase (TA), we have accomplished the direct synthesis of multiple medium and long chain primary fatty amines in one pot with analytical yields as high as 97 %. We have also performed a 75 mL preparative scale reaction for the synthesis of laurylamine from trilaurin, obtaining 73 % isolated yield.
- Citoler, Joan,Finnigan, William,Bevinakatti, Han,Turner, Nicholas J.
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- Development and Application of Efficient Ag-based Hydrogenation Catalysts Prepared from Rice Husk Waste
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The development of strategies for the sustainable management and valorization of agricultural waste is of outmost importance. With this in mind, we report the use of rice husk (RH) as feedstock for the preparation of heterogeneous catalysts for hydrogenation reactions. The catalysts were prepared by impregnating the milled RH with a silver nitrate solution followed by carbothermal reduction. The composition and morphology of the prepared catalysts were fully assessed by IR, AAS, ICP-MS, XPS, XRD and STEM techniques. This novel bio-genic silver-based catalysts showed excellent activity and remarkable selectivity in the hydrogenation of nitro groups in both aromatic and aliphatic substrates, even in the presence of reactive functionalities like halogens, carbonyls, borate esters or nitriles. Recycling experiments showed that the catalysts can be easily recovered and reused multiple times without significant drop in performance and without requiring re-activation.
- Unglaube, Felix,Kreyenschulte, Carsten Robert,Mejía, Esteban
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p. 2583 - 2591
(2021/04/09)
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- A State-of-the-Art Heterogeneous Catalyst for Efficient and General Nitrile Hydrogenation
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Cobalt-doped hybrid materials consisting of metal oxides and carbon derived from chitin were prepared, characterized and tested for industrially relevant nitrile hydrogenations. The optimal catalyst supported onto MgO showed, after pyrolysis at 700 °C, magnesium oxide nanocubes decorated with carbon-enveloped Co nanoparticles. This special structure allows for the selective hydrogenation of diverse and demanding nitriles to the corresponding primary amines under mild conditions (e.g. 70 °C, 20 bar H2). The advantage of this novel catalytic material is showcased for industrially important substrates, including adipodinitrile, picolinonitrile, and fatty acid nitriles. Notably, the developed system outperformed all other tested commercial catalysts, for example, Raney Nickel and even noble-metal-based systems in these transformations.
- Formenti, Dario,Mocci, Rita,Atia, Hanan,Dastgir, Sarim,Anwar, Muhammad,Bachmann, Stephan,Scalone, Michelangelo,Junge, Kathrin,Beller, Matthias
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supporting information
p. 15589 - 15595
(2020/10/02)
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- A cobalt phosphide catalyst for the hydrogenation of nitriles
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The study of metal phosphide catalysts for organic synthesis is rare. We present, for the first time, a well-defined nano-cobalt phosphide (nano-Co2P) that can serve as a new class of catalysts for the hydrogenation of nitriles to primary amines. While earth-abundant metal catalysts for nitrile hydrogenation generally suffer from air-instability (pyrophoricity), low activity and the need for harsh reaction conditions, nano-Co2P shows both air-stability and remarkably high activity for the hydrogenation of valeronitrile with an excellent turnover number exceeding 58000, which is over 20- to 500-fold greater than that of those previously reported. Moreover, nano-Co2P efficiently promotes the hydrogenation of a wide range of nitriles, which include di- and tetra-nitriles, to the corresponding primary amines even under just 1 bar of H2 pressure, far milder than the conventional reaction conditions. Detailed spectroscopic studies reveal that the high performance of nano-Co2P is attributed to its air-stable metallic nature and the increase of the d-electron density of Co near the Fermi level by the phosphidation of Co, which thus leads to the accelerated activation of both nitrile and H2. Such a phosphidation provides a promising method for the design of an advanced catalyst with high activity and stability in highly efficient and environmentally benign hydrogenations. This journal is
- Jitsukawa, Koichiro,Mitsudome, Takato,Mizugaki, Tomoo,Nakata, Ayako,Sheng, Min,Yamasaki, Jun
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p. 6682 - 6689
(2020/08/24)
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- One-pot reductive amination of carboxylic acids: a sustainable method for primary amine synthesis
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The reductive amination of carboxylic acids is a very green, efficient and sustainable method for the production of (bio-based) amines. However, with current technology, this reaction requires two to three reaction steps. Here, we report the first (heterogeneous) catalytic system for the one-pot reductive amination of carboxylic acids to amines, with solely H2 and NH3 as the reactants. This reaction can be performed with relatively cheap ruthenium-tungsten bimetallic catalysts in the green and benign solvent cyclopentyl methyl ether (CPME). Selectivities of up to 99% for the primary amine could be achieved at high conversions. Additionally, the catalyst is recyclable and tolerant for common impurities such as water and cations (e.g. sodium carboxylate).
- Coeck, Robin,De Vos, Dirk E.
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supporting information
p. 5105 - 5114
(2020/08/25)
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- A biocatalytic cascade for the conversion of fatty acids to fatty amines
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Fatty amine synthesis from renewable sources is an energetically-demanding process involving toxic metal catalysts and harsh reaction conditions as well as selectivity problems. Herein we present a mild, biocatalytic alternative to the conventional amination of fatty acids through a one-pot tandem cascade performed by a carboxylic acid reductase (CAR) and a transaminase (ω-TA). Saturated and unsaturated fatty acids, with carbon chain lengths ranging from C6 to C18, were successfully aminated obtaining conversions of up to 96%.
- Citoler, Joan,Derrington, Sasha R.,Galman, James L.,Bevinakatti, Han,Turner, Nicholas J.
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supporting information
p. 4932 - 4935
(2019/09/30)
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- Iron-Catalyzed Intramolecular Amination of Aliphatic C-H Bonds of Sulfamate Esters with High Reactivity and Chemoselectivity
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It is challenging to develop simple and low cost catalytic systems while maintaining high reactivity and selectivity. An iron-catalyzed intramolecular C-H amination of sulfamate esters using simple and cheap ligands is reported with general substrate scope (31 examples, up to 95% yield). The addition of second ligand, bipyridine, is able to accelerate the reaction and increase the yield. The ready availability of these iron catalysts provides a promising approach to selective introduction of nitrogen into hydrocarbon feedstock.
- Liu, Wei,Zhong, Dayou,Yu, Cheng-Long,Zhang, Yan,Wu, Di,Feng, Ya-Lan,Cong, Hengjiang,Lu, Xiuqiang,Liu, Wen-Bo
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p. 2673 - 2678
(2019/04/30)
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- Deacetylative Amination of Acetyl Arenes and Alkanes with C-C Bond Cleavage
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The Br?nsted acid-catalyzed synthesis of primary amines from acetyl arenes and alkanes with C-C bond cleavage is described. Although the conversion from an acetyl group to amine has traditionally required multiple steps, the method described herein, which uses an oxime reagent as an amino group source, achieves the transformation directly via domino transoximation/Beckmann rearrangement/Pinner reaction. The method was also applied to the synthesis of γ-aminobutyric acids, such as baclophen and rolipram.
- Hyodo, Kengo,Hasegawa, Genna,Maki, Hiroya,Uchida, Kingo
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supporting information
p. 2818 - 2822
(2019/04/25)
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- Selective Transformations of Triglycerides into Fatty Amines, Amides, and Nitriles by using Heterogeneous Catalysis
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The use of triglycerides as an important class of biomass is an effective strategy to realize a more sustainable society. Herein, three heterogeneous catalytic methods are reported for the selective one-pot transformation of triglycerides into value-added chemicals: i) the reductive amination of triglycerides into fatty amines with aqueous NH3 under H2 promoted by ZrO2-supported Pt clusters; ii) the amidation of triglycerides under gaseous NH3 catalyzed by high-silica H-beta (Hβ) zeolite at 180 °C; iii) the Hβ-promoted synthesis of nitriles from triglycerides and gaseous NH3 at 220 °C. These methods are widely applicable to the transformation of various triglycerides (C4–C18 skeletons) into the corresponding amines, amides, and nitriles.
- Jamil, Md. A. R.,Siddiki, S. M. A. Hakim,Touchy, Abeda Sultana,Rashed, Md. Nurnobi,Poly, Sharmin Sultana,Jing, Yuan,Ting, Kah Wei,Toyao, Takashi,Maeno, Zen,Shimizu, Ken-ichi
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p. 3115 - 3125
(2019/04/26)
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- Selective Synthesis of Primary Amines from Nitriles under Hydrogenation Conditions
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The hydrogenation of aliphatic nitriles over Pd/C, Pd/Al2O3, and Pd?Au/Al2O3 catalysts were evaluated for the selective hydrogenation of aliphatic nitriles to the corresponding primary amines. The highest selectivity (>99%) toward primary amines was achieved when the reaction was carried out in acetic acid using 10 mol% of 25% Pd-5% Au/Al2O3 under relatively low hydrogen pressure (0.8 MPa). Characterization of the catalysts by XRD, CO adsorption experiments, and EXAFS revealed that the excellent selectivity of 25% Pd-5% Au/Al2O3 toward the synthesis of primary amines is determined by the electronic properties and/or the surface structure resulting from alloying Pd with Au. (Figure presented.).
- Yoshimura, Masatoshi,Komatsu, Akira,Niimura, Masaru,Takagi, Yukio,Takahashi, Tohru,Ueda, Shun,Ichikawa, Tomohiro,Kobayashi, Yutaka,Okami, Hiroki,Hattori, Tomohiro,Sawama, Yoshinari,Monguchi, Yasunari,Sajiki, Hironao
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supporting information
p. 1726 - 1732
(2018/03/21)
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- Cobalt-based nanoparticles prepared from MOF-carbon templates as efficient hydrogenation catalysts
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The development of efficient and selective nanostructured catalysts for industrially relevant hydrogenation reactions continues to be an actual goal of chemical research. In particular, the hydrogenation of nitriles and nitroarenes is of importance for the production of primary amines, which constitute essential feedstocks and key intermediates for advanced chemicals, life science molecules and materials. Herein, we report the preparation of graphene shell encapsulated Co3O4- and Co-nanoparticles supported on carbon by the template synthesis of cobalt-terephthalic acid MOF on carbon and subsequent pyrolysis. The resulting nanoparticles create stable and reusable catalysts for selective hydrogenation of functionalized and structurally diverse aromatic, heterocyclic and aliphatic nitriles, and as well as nitro compounds to primary amines (>65 examples). The synthetic and practical utility of this novel non-noble metal-based hydrogenation protocol is demonstrated by upscaling several reactions to multigram-scale and recycling of the catalyst.
- Murugesan, Kathiravan,Senthamarai, Thirusangumurugan,Sohail, Manzar,Alshammari, Ahmad S.,Pohl, Marga-Martina,Beller, Matthias,Jagadeesh, Rajenahally V.
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p. 8553 - 8560
(2018/11/30)
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- Hierarchy of Asymmetry at Work: Chain-Dependent Helix-to-Helix Interactions in Supramolecular Polymers
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A detailed investigation of the hierarchy of asymmetry operating in the self-assembly of achiral (1) and chiral ((S)-2 and (R)-3) 1,3,5-triphenylbenzenetricarboxamides (TPBAs) is reported. The aggregation of these TPBAs is conditioned by the point chirality at the peripheral side chains for (S)-2 and (R)-3. An efficient helix-to-helix interaction that goes further in the organization of fibrillar bundles is experimentally detected and theoretically supported only for the achiral TPBA 1. The effective interdigitation of the achiral aliphatic side chains produces a social self-sorting to form preferentially heterochiral macromolecular aggregates.
- Díaz-Cabrera, Sandra,Dorca, Yeray,Calbo, Joaquín,Aragó, Juan,Gómez, Rafael,Ortí, Enrique,Sánchez, Luis
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supporting information
p. 2826 - 2831
(2018/02/09)
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- Selective Hydrogenation of Nitriles to Primary Amines by using a Cobalt Phosphine Catalyst
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A general procedure for the catalytic hydrogenation of nitriles to primary amines by using a non-noble metal-based system is presented. Co(acac)3 in combination with tris[2-(dicyclohexylphosphino)ethyl]phosphine efficiently catalyzes the selective hydrogenation of a wide range of (hetero)aromatic and aliphatic nitriles to give the corresponding amines.
- Adam, Rosa,Bheeter, Charles Beromeo,Cabrero-Antonino, Jose R.,Junge, Kathrin,Jackstell, Ralf,Beller, Matthias
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p. 842 - 846
(2017/03/17)
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- Catalyst-Dependent Selective Hydrogenation of Nitriles: Selective Synthesis of Tertiary and Secondary Amines
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In the presence of palladium on carbon (Pd/C) as a catalyst, hydrogenation of aliphatic nitriles in cyclohexane efficiently proceeded at 25-60 °C under ordinary hydrogen gas pressure to afford the corresponding tertiary amines. However, the use of rhodium on carbon (Rh/C) led to the highly selective generation of secondary amines. Hydrogenation of aromatic nitriles and cyclohexanecarbonitrile selectively produced secondary amines in the presence of either Pd/C or Rh/C.
- Monguchi, Yasunari,Mizuno, Masahiro,Ichikawa, Tomohiro,Fujita, Yuki,Murakami, Eri,Hattori, Tomohiro,Maegawa, Tomohiro,Sawama, Yoshinari,Sajiki, Hironao
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p. 10939 - 10944
(2017/10/27)
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- Reduced reactivity of amines against nucleophilic substitution via reversible reaction with carbon dioxide
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The reversible reaction of carbon dioxide (CO2) with primary amines to form alkyl-ammonium carbamates is demonstrated in this work to reduce amine reactivity against nucleophilic substitution reactions with benzophenone and phenyl isocyanate. The reversible formation of carbamates has been recently exploited for a number of unique applications including the formation of reversible ionic liquids and surfactants. For these applications, reduced reactivity of the carbamate is imperative, particularly for applications in reactions and separations. In this work, carbamate formation resulted in a 67% reduction in yield for urea synthesis and 55% reduction for imine synthesis. Furthermore, the amine reactivity can be recovered upon reversal of the carbamate reaction, demonstrating reversibility. The strong nucleophilic properties of amines often require protection/de-protection schemes during bi-functional coupling reactions. This typically requires three separate reaction steps to achieve a single transformation, which is the motivation behind Green Chemistry Principle #8: Reduce Derivatives. Based upon the reduced reactivity, there is potential to employ the reversible carbamate reaction as an alternative method for amine protection in the presence of competing reactions. For the context of this work, CO2 is envisioned as a green protecting agent to suppress formation of n-phenyl benzophenoneimine and various n-phenyl-n-alky ureas.
- Mohammed, Fiaz S.,Kitchens, Christopher L.
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- Amination of ω-Functionalized Aliphatic Primary Alcohols by a Biocatalytic Oxidation-Transamination Cascade
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Amination of non-activated aliphatic fatty alcohols to the corresponding primary amines was achieved through a five-enzyme cascade reaction by coupling a long-chain alcohol oxidase from Aspergillus fumigatus (LCAO-Af) with a ω-transaminase from Chromobacterium violaceum (ω-TA-Cv). The alcohol was oxidized at the expense of molecular oxygen to yield the corresponding aldehyde, which was subsequently aminated by the PLP-dependent ω-TA to yield the final primary amine product. The overall cascade was optimized with respect to pH, O2 pressure, substrate concentration, decomposition of H2O2 (derived from alcohol oxidation), NADH regeneration, and biocatalyst ratio. The substrate scope of this concept was investigated under optimized conditions by using terminally functionalized C4-C11 fatty primary alcohols bearing halogen, alkyne, amino, hydroxy, thiol, and nitrile groups.
- Pickl, Mathias,Fuchs, Michael,Glueck, Silvia M.,Faber, Kurt
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p. 3121 - 3124
(2015/10/19)
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- Fe3O4-SiO2-P4VP pH-sensitive microgel for immobilization of nickel nanoparticles: An efficient heterogeneous catalyst for nitrile reduction in water
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Fe3O4 magnetic nanoparticles (MNPs) were modified with (3-aminopropyl)triethoxysilane through silanization. An atom transfer radical polymerization-initiating site immobilized onto amine-functionalized Fe3O4 MNPs. The surface-initiated atom transfer radical polymerization of 4-vinylpyridine was then performed in the presence of Fe 3O4-SiO2-Br nanoparticles, which led to the formation of Fe3O4-SiO2-P4VP [P4VP=poly(4-vinylpyridine)] hybrid microgels cross-linked with Fe 3O4 MNPs. Our approach uses polymer microgels as templates for the synthesis of nickel nanoparticles (NiNPs). The tunable properties of synthesized NiNPs@Fe3O4-SiO2-P4VP pH-sensitive microgels were used in the catalytic reduction of aliphatic and aromatic nitriles. Moreover, the catalytic activity of metal nanocomposites that can be modulated by the volume transition of microgel structures with changing pH has been evaluated. TEM, X-ray photoelectron spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, XRD, UV/Vis spectroscopy, and FTIR spectroscopy were used to characterize the resultant catalyst. Mystery solved: Our approach uses polymer microgels as templates for the synthesis of nickel nanoparticles. The tunable properties of synthesized NiNPs@Fe3O 4-SiO2-P4VP [NiNPs=nickel nanoparticles; P4VP=poly(4-vinylpyridine)] pH-sensitive microgels are used in the catalytic reduction of aliphatic and aromatic nitriles. Moreover, the catalytic activity of metal nanocomposites that can be modulated by the volume transition of microgel structures with changing pH has been evaluated. Copyright
- Nabid, Mohammad Reza,Bide, Yasamin,Niknezhad, Mahvash
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p. 538 - 546
(2014/03/21)
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- Systematic evaluation of the palladium-catalyzed hydrogenation under flow conditions
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Four types of heterogeneous Pd catalysts (10% Pd/C, 10% Pd/HP20, 0.5% Pd/MS3A, and 0.3% Pd/BN) were applied to the flow hydrogenation to systematically evaluate the appropriate conditions for the reduction of a wide variety of reducible functionalities. The use of 10% Pd/C and 10% Pd/HP20 allowed the hydrogenation of various reducible functionalities by a single-pass of the substrate-MeOH solution through the catalyst cartridge, while 0.5% Pd/MS3A and 0.3% Pd/BN catalyzed a novel chemoselective hydrogenation; only alkene, alkyne, azide, and nitro functionalities could be reduced with other coexisting reducible functionalities intact.
- Hattori, Tomohiro,Tsubone, Aya,Sawama, Yoshinari,Monguchi, Yasunari,Sajiki, Hironao
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p. 4790 - 4798
(2014/06/24)
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- Two iron catalysts are better than one: A general and convenient reduction of aromatic and aliphatic primary amides
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It takes two: For the reduction of amides to amines iron catalysts were developed. A combination of two different iron catalysts made possible the challenging reduction of primary amides (see picture). Copyright
- Das, Shoubhik,Wendt, Bianca,Moeller, Konstanze,Junge, Kathrin,Beller, Matthias
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supporting information; experimental part
p. 1662 - 1666
(2012/05/05)
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- Redox self-sufficient biocatalyst network for the amination of primary alcohols
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Driving the machinery: A biocatalytic redox-neutral cascade for the preparation of terminal primary amines from primary alcohols at the expense of ammonia has been established in a one-pot one-step method (see picture). Applying this artificial biocatalyst network, long-chain 1,ω-alkanediols were converted into diamines, which are building blocks for polymers, in up to 99 % conversion. Copyright
- Sattler, Johann H.,Fuchs, Michael,Tauber, Katharina,Mutti, Francesco G.,Faber, Kurt,Pfeffer, Jan,Haas, Thomas,Kroutil, Wolfgang
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supporting information
p. 9156 - 9159
(2012/10/30)
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- Salt suitable for an acid generator and a chemically amplified positive resist composition containing the same
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The present invention provides a salt represented by the formula (I): wherein P1, P2 and P3 each independently represent a C1-C30 alkyl group which may be substituted with at least one selected from a hydroxyl group, a C3-C12 cyclic hydrocarbon group and a C1-C12 alkoxy group, or a C3-C30 cyclic hydrocarbon group which may be substituted with at least one selected from a hydroxyl group and a C1-C12 alkoxy group, provided that all of P1, P2 and P3 are not simultaneously phenyl groups which may be substituted, Q1 and Q2 each independently represent a fluorine atom or a C1-C6 perfluoroalkyl group, and R represents a group represented by the formula: wherein A1 represents —OH or —Y1—OH, n represents an integer of 1 to 9, and Y1 represents a divalent C1-C6 saturated aliphatic hydrocarbon group; a group represented by the formula: wherein ring X1 represents a C3-C30 monocyclic or polycyclic hydrocarbon group in which one —CH2— group is substituted with —CO—, and at least one hydrogen atom in the monocyclic or polycyclic hydrocarbon group may be substituted with a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C4 perfluoroalkyl group, a C1-C6 hydroxyalkyl group, a hydroxyl group or a cyano group; a group represented by the formula: wherein ring X2 represents a C3-C30 monocyclic or polycyclic hydrocarbon group in which a hydrogen atom of one —CH2— group is substituted with a hydroxyl group, and at least one hydrogen atom in the monocyclic or polycyclic hydrocarbon group may be substituted with a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C4 perfluoroalkyl group, a C1-C6 hydroxyalkyl group, a hydroxyl group or a cyano group; a group represented by the formula: wherein ring X3 represents a C3-C30 monocyclic or polycyclic hydrocarbon group in which one —CH2— group is substituted with —COO—, and at least one hydrogen atom in the monocyclic or polycyclic hydrocarbon group may be substituted with a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C4 perfluoroalkyl group, a C1-C6 hydroxyalkyl group, a hydroxyl group or a cyano group, and m represents an integer of 0 to 12; or a group represented by the formula: wherein ring X4 represents a C6-C30 polycyclic hydrocarbon group having tricycle or more, and at least one hydrogen atom in the polycyclic hydrocarbon group may be substituted with a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C4 perfluoroalkyl group, a C1-C6 hydroxyalkyl group or a cyano group, and l represents an integer of 1 to 12. The present invention further provides a chemically amplified resist composition comprising the salt represented by the above-mentioned formula (I).
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- Efficient transformation of azides to primary amines using the mild and easily accessible CeCl3·;7H2O/NaI system
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(Chemical Equation Presented) Because of the nitrogen functionality, the azido group plays an important role in the synthesis of amines, and numerous reduction methods of azides to primary amines are reported. Recent reports have highlighted the capability of NaI as a useful reagent for this transformation when it is used in combination with a Lewis acid promoter. However, these methods often suffer from harsh reaction conditions; for this reason, the development of a simple and efficient protocol using NaI in presence of inexpensive and readily available cerium salts Lewis acids would extend the scope of this organic transformation. In continuation of our interest on the use of the CeCl3·7H2O/NaI system, in this paper we report how azides undergo reduction by NaI in the presence of CeCl 3·7H2O in refluxing acetonitrile under neutral conditions to produce the corresponding primary amines. The rate and yield of the reaction are considerably improved by employing this microwave-assisted procedure, and this may be of value for the preparation of densely functionalized molecules having biological and pharmaceutical activities.
- Bartoli, Giuseppe,Di Antonio, Giustino,Giovannini, Riccardo,Giuli, Sandra,Lanari, Silvia,Paoletti, Melissa,Marcantoni, Enrico
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p. 1919 - 1924
(2008/09/18)
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- Low-temperature deacylation of N-monosubstituted amides
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(Chemical Equation Presented) The (PhO)3P-Cl2 reagent, prepared in situ by titrating a solution of triphenyl phosphite with chlorine, is used to convert N-monosubstituted amides into their corresponding amines. The reaction, if compared to other traditional methods, shows the advantage of very mild conditions and low temperature (-30°C→rt).
- Spaggiari, Alberto,Blaszczak, Larry C.,Prati, Fabio
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p. 3885 - 3888
(2007/10/03)
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- Amino group-containing thiols and method for production thereof
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These amino group-containing mono- or dithiols are represented by formula (I). In order to prepare them, ethylene sulfide is reacted with at least one compound of formula (II), the average number of moles of ethylene sulfide added corresponding to the total m+n, and possibly the compound of formula (I) as obtained is further reacted with ethylene sulfide in order to increase the value of m+n. R1 stands for a straight or branched alkyl or alkenyl group having 10 to 30 carbon atoms; R2 stands for a straight or branched alkyl or alkenyl group having 10 to 30 carbon atoms, or a —(CH2—CH2—S)n—H group; m and n, which are identical or different, each represent 0 or an integer in the range of 1 to 10 and satisfy 1.62 stands for a hydrogen atom in which case R2 in formula (I) will represent —(CH2—CH2—S)n—H, or a straight or branched alkyl or alkenyl group having 10 to 30 carbon atoms, in which case it will remain unchanged in the compound of the formula (I).
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- Cyanoguanidines as cell proliferation inhibitors
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The present invention relates to hitherto unknown compounds of formula (I) or their tautomeric forms, the attachment to the pyridine being in the 3- or 4-position, in which formula R1 stands for one or more substituents which can be the same or different and are selected from the group consisting of: hydrogen, halogen, trifluoromethyl nitro, amino, cyano, carboxy, or alkyl, alkoxy, or alkoxycarbonyl, the C-content of which can be from 1 to 4; X stands for a straight or branched C9-C20 carbon chain, saturated or unsaturated or Q—Ar—R; in which formula Ar stands for phenyl, Q stands for a C5-C20 divalent hydrocarbon radical which can be straight, branched, saturated or unsaturated and R stands for hydrogen or for one or more substituents which can be the same or different and are selected from the group consisting of: hydroxy, amino, halogen, trifluoromethyl, cyano, nitro, carboxy, carbamoyl, or alkyl, alkoxy, alkylthio, alkylamino, or alkoxycarbonyl, the C-content of which can be from 1 to 4; and pharmaceutically acceptable, non-toxic salts and N-oxides thereof. The present compounds are of value in the human and veterinary practice.
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- Indium Mediated Reduction of Nitro and Azide Groups in the Presence of HCl in Aqueous Media
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Indium mediated reduction of azide and nitro groups in the presence of HCl (1.5 equiv based on indium) at room temperature in aqueous THF successfully provided the corresponding amine in high to quantitative yields. Under the some reaction conditions, selective reduction of azide and nitro group in the presence of vinyl group could be accomplished.
- Lee, Jung Gyu,Choi, Kyung Il,Koh, Hun Yeong,Kim, Youseung,Kang, Yonghan,Cho, Yong Seo
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- A facile route to the deprotection of sulfonate esters and sulfonamides with low valent titanium reagents
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A novel method for the cleavage of N/O-tosyl bonds by low-valent titanium is reported. TBDPS ether, THP ether, and olefin are found to be compatible under the reaction conditions.
- Nayak
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p. 1575 - 1578
(2007/10/03)
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- A facile radical induced selective removal of N-propargyl protecting groups using low valent titanium reagents
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Low valent titanium mediated cleavage of N-propargyl bonds offers a facile, mild, and high yielding method for the deprotection of amines under neutral conditions. The methodology could be used for the chemoselective removal of propargyl groups from amines in preference to the allyl/benzyl counterparts and can be performed chemoselectively in the presence of methoxy, methylenedioxy, and chloro functionalities.
- Rele, Shyam,Talukdar, Sanjay,Banerji, Asoke
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p. 767 - 770
(2007/10/03)
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- Efficient Reduction of Azides with Samarium Diiodide
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Reduction of alkyl, aryl and aroyl azides to the parent primary amines or amides, respectively, occurs in good yield upon treatment with an excess of SmI2 in THF at room temperature.A radical mechanism is proposed.
- Goulaouic-Dubois, Catherine,Hesse, Manfred
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p. 7427 - 7430
(2007/10/02)
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- PREPARATION OF ISOMERICALLY PURE ALKYLAMINES VIA THE REACTION OF DIMETHYLALKYLBORANES WITH CHLORAMINE
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Dimethylborane was used to hydroborate alkenes regiospecifically.The resultant dimethylalkylboranes react with ammonium hydrochloride and sodium hypochlorite to yield isomerically pure alkylamines.
- Kabalka, George W.,Wang, Zhe,Goudgaon, Nganna M.
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p. 2409 - 2414
(2007/10/02)
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- A Facile Reduction of Azides to Amines Using Hydrazine
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A variety of alkyl and aryl azides were reduced in high yields to the corresponding amines by reaction with hydrazine in refluxing methanol in the presence of palladium.
- Malik, A. A.,Preston, S. B.,Archibald, T. G.,Cohen, M. P.,Baum, K.
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p. 450 - 451
(2007/10/02)
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- ALKALINE EARTH METAL MEDIATED REDUCTION OF AZIDES TO AMINES
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A mild and facile method for the reduction of alkyl and aryl azides to the corresponding amines using alkaline earth metals is described.
- Maiti, Samarendra N.,Spevak, Paul,Reddy, A. V. Narender
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p. 1201 - 1206
(2007/10/02)
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- Reaction of organoboranes with hydrazoic acid
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Organoboranes react with sodium azide in the presence of aqueous acid to yield primary amines. The reaction presumably proceeds via the anionotropic rearrangement of an organoborate complex.
- Kabalka, George W.,Henderson, David A.,Varma, Rajender S.
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p. 1369 - 1370
(2008/10/08)
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- ORGANOBORANES FOR SYNTHESIS. 7. AN IMPROVED GENERAL SYNTHESIS OF PRIMARY AMINES FROM ALKENES via HYDROBORATION-ORGANOBORANE CHEMISTRY
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Triorganylboranes, R3B, and diorganylborinicesters, R2BOR', react readily with preformed chloramine or hydroxylamine-O-sulfonic acid to produce the corresponding primary amines, RNH2.However, the product of the reaction following hydrolysis is the boronic acid, RB(OH)2, limiting the yield to 67percent for R3B and to 50percent for R2BOR'.This problem has now been overcome with the help of lithium dimethylborohydride, readily converted in situ to dimethylborane.The hydroboration of representative alkenes by dimethylborane provides the corresponding monoorganyldimethylborane, RMe2B.Treatment of this intermediate with hydroxylamine-O-sulfonic acid provides the desired amines, RNH2, in isolated yields of 73percent to 95percent.The reaction proceeds with complete retention, reproducing the precise structure of the organic group in the organoboranes, RMe2B.
- Brown, Herbert C.,Kim, Kee-Won,Srebnik, Morris,Singaram, Bakthan
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p. 4071 - 4078
(2007/10/02)
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- FACILE CONVERSION OF AZIDES TO AMINES
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A simple method for the reduction of azides to primary amines is described.
- Maiti, Samarendra N.,Singh, Maya P.,Micetich, Ronald G.
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p. 1423 - 1424
(2007/10/02)
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- Derivatives of leukotrienes A and C
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The present invention provides novel derivatives of leukotrienes A and C which are useful in inhibiting the smooth muscle contracting effects of SRS-A; inhibiting platelet aggregation; and inhibiting the biosynthesis of thromboxane A2.
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- Aminoborohydrides as Reducing Agents. 1. Sodium (Dimethylamino)- and (tert-Butylamino)borohydrides as Selective Reducing Agents
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Replacement of a hydride in borohydride by an electron-donating alkylamino group greatly enhances the reducing ability of the resulting reagents.Thus, sodium (dimethylamino)- and (tert-butylamino)borohydrides (1, NaDMAB, and 2, NaTBAB, respectively) not only reduce aldehydes and ketones to alcohols but also are effective for the conversion of esters to alcohols and primary amides to amines in good to excellent yields.Tertiary amides are reduced to alcohols (i.e., N,N-dimethylamides) or amines (i.e.N,N-diisopropylamides) depending on the steric bulk of the alkyl substituents on nitrogen.However, secondary amides are not reduced by the reagents allowing selective conversion of primary and tertiary amides in the presence of secondary amides.Nitriles are attacked by the reagents but do not afford synthetically useful amounts of amine products.Aryl halides are slowly converted to arenes, but alkyl halides and epoxides undergo unusual reactions with the amino portion of the reagents.
- Hutchins, Robert O.,Learn, Keith,El-Telbany, Farag,Stercho, Yuriy P.
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p. 2438 - 2443
(2007/10/02)
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- AN EXCEPTIONALLY MILD DEPROTECTION OF PHTHALIMIDES
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Phthalimides are converted to primary amines in an efficient, two-stage, one-flask operation using NaBH4/2-propanol, then acetic acid.
- Osby, John O.,Martin, Michael G.,Ganem, Bruce
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p. 2093 - 2096
(2007/10/02)
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- Quaternary alkynoxymethyl amines
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This invention relates to quaternaries of alkynoxymethyl amines and uses thereof. These may be summarized by the following formulae: STR1 where R and R' are substituted groups such as alkyl, aryl, etc.; R'" is an acetylenic group; and X is an anion; and STR2 where R and R'" having the same meaning as in (1) and Z is a bridging group, preferably hydrocarbon such as alkylene, alkinylene, alkenylene, arylene, etc.
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- A NEW PROTECTING GROUP FOR AMINES. SYNTHESIS OF ANTICAPSIN FROM L-TYROSINE
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An acid and base-stable, nucleophile-resistant protecting group for primary amines and α-amino acids is described which has been used in a synthesis of the title compound.
- Laguzza, Bennett C.,Ganem, Bruce
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p. 1483 - 1486
(2007/10/02)
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- Microbiocidal quaternaries of halogen derivatives of alkynoxymethyl amines
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This invention relates to quaternaries of halogen derivatives of alkynoxymethyl amines and uses thereof. These may be summarized by the following formulae: STR1 where R and R' are substituted groups such as alkyl, aryl, etc.; R" is an alkylidene group; and X is halogen and A is an anion; and STR2 where R, R' and R" having the same meaning as in (1) and Z is a bridging group, preferably hydrocarbon such as alkylene, alkinylene, alkenylene, arylene, etc.
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- 19-Hydroxy-PGI2 compounds
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Prostacyclin and prostacyclin-type derivatives having a 19-hydroxy feature are disclosed, including processes for preparing them and the appropriate intermediates. The compounds are useful for pharmacological purposes such as inhibition of blood platelate aggregation.
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- 2-Decarboxy-2-hydroxymethyl-19-hydroxy-PG1 analogs
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Prostaglandin derivatives having a 19,20-didehydro, a 19-hydroxy, or a 19-keto feature are disclosed, including processes for preparing them and the appropriate intermediates. A typical 19-hydroxy compound of this invention is 19-hydroxy-19-methyl-PGF2α, methyl ester, represented by the formula STR1
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