- Organic photoredox catalytic α-C(sp3)-H phosphorylation of saturated: Aza -heterocycles
-
A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Br?nsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.
- Yi, Ming-Jun,Xiao, Teng-Fei,Li, Wen-Hui,Zhang, Yi-Fan,Yan, Pen-Ji,Zhang, Baoxin,Xu, Peng-Fei,Xu, Guo-Qiang
-
supporting information
p. 13158 - 13161
(2021/12/16)
-
- Catalyst-free photodecarbonylation ofortho-amino benzaldehyde
-
It is almost a consensus that decarbonylation of the aldehyde group (-CHO) needs to not only be mediated by transition metal catalysts, but also requires severe reaction conditions (high temperature and long reaction time). In this work, inspired by the “conformational-selectivity-based” design strategy, we broke this consensus and discovered a catalyst-free photodecarbonylation of the aldehyde group. It revealed that decarbonylation can be easily achieved with visible light irradiation by introducing a tertiary amine into theortho-position of the aldehyde group. A diverse array of tertiary amines is tolerated by our photodecarbonylation under mild conditions. Furthermore, the (QM) computations of the mechanism and the experiments on well-designed special substrates revealed that our photodecarbonylation depends on the conformational specificity of the aldehyde group and tertiary amine, and occurs through an unusual [1,4]-H shift and a subsequent [1,3]-H shift.
- Li, Lamei,Wang, Songping,Wei, Wentao,Yan, Ming,Zhou, Jingwei
-
supporting information
p. 3421 - 3426
(2020/06/25)
-
- Electron Donor-Acceptor Complex-Initiated Photochemical Cyanation for the Preparation of α-Amino Nitriles
-
An electron donor-acceptor complex-initiated α-cyanation of tertiary amines has been described. The reaction protocol provides a novel method to synthesize various α-amino nitriles under mild conditions. The reaction can proceed smoothly without the presence of photocatalysts and transition metal catalysts, and either oxidants are unnecessary or O2 is the only oxidant. The practicality of this method is showcased not only by the late-stage functionalization of natural alkaloid derivatives and pharmaceutical intermediate, but also by the applicability of a stop-flow microtubing reactor.
- Xia, Qing,Li, Yufei,Cheng, Lan,Liang, Xin,Cao, Chenlin,Dai, Peng,Deng, Hongping,Zhang, Weihua,Wang, Qingmin
-
supporting information
p. 9638 - 9643
(2020/12/21)
-
- Metal-Free Synthesis of N-Aryl-Substituted Azacycles from Cyclic Ethers Using POCl3
-
A facile method for the synthesis of N-aryl-substituted azacycles from arylamines and cyclic ethers has been developed. In this study, arylamines were treated with cyclic ethers in the presence of POCl3 and DBU to provide five- A nd six-membered azacycles. Using this method, various azacycloalkanes, isoindolines, and tetrahydroisoquinolines were prepared in high yields. This synthetic method offers an efficient approach to the production of azacycles from cyclic ethers.
- La, Minh Thanh,Kang, Soosung,Kim, Hee-Kwon
-
p. 6689 - 6696
(2019/06/14)
-
- Practical and regioselective amination of arenes using alkyl amines
-
The formation of carbon–nitrogen bonds for the preparation of aromatic amines is among the top five reactions carried out globally for the production of high-value materials, ranging from from bulk chemicals to pharmaceuticals and polymers. As a result of this ubiquity and diversity, methods for their preparation impact the full spectrum of chemical syntheses in academia and industry. In general, these molecules are assembled through the stepwise introduction of a reactivity handle in place of an aromatic C–H bond (that is, a nitro group, halogen or boronic acid) and a subsequent functionalization or cross-coupling. Here we show that aromatic amines can be constructed by direct reaction of arenes and alkyl amines using photocatalysis, without the need for pre-functionalization. The process enables the easy preparation of advanced building blocks, tolerates a broad range of functionalities, and multigram scale can be achieved via a batch-to-flow protocol. The merit of this strategy as a late-stage functionalization platform has been demonstrated by the modification of several drugs, agrochemicals, peptides, chiral catalysts, polymers and organometallic complexes.
- Ruffoni, Alessandro,Juliá, Fabio,Svejstrup, Thomas D.,McMillan, Alastair J.,Douglas, James J.,Leonori, Daniele
-
p. 426 - 433
(2019/05/01)
-
- Robust Buchwald-Hartwig amination enabled by ball-milling
-
An operationally simple mechanochemical method for the Pd catalysed Buchwald-Hartwig amination of arylhalides with secondary amines has been developed using a Pd PEPPSI catalyst system. The system is demonstrated on 30 substrates and applied in the context of a target synthesis. Furthermore, the performance of the reaction under aerobic conditions has been probed under traditional solution and mechanochemical conditions, the observations are discussed herein.
- Cao, Qun,Nicholson, William I.,Jones, Andrew C.,Browne, Duncan L.
-
supporting information
p. 1722 - 1726
(2019/02/20)
-
- Nickel-Catalyzed Reductive Cleavage of Carbon-Oxygen Bonds in Anisole Derivatives Using Diisopropylaminoborane
-
The catalytic removal of a methoxy group on an aromatic ring allows this group to be used as a traceless activating and directing group for aromatic functionalization reactions. Although several catalytic methods for the reductive cleavage of anisole derivatives have been reported, all are applicable only to π-extended aryl ethers, such as naphthyl and biphenyl ethers, while monocyclic aryl ethers cannot be reduced. Herein, we report a nickel-catalyzed reductive cleavage reaction of C-O bonds in aryl ethers using diisopropylaminoborane as the reducing agent. Unlike previously reported methods, this reducing reagent allows effective C-O bond reduction in a much wider range of aryl ether substrates, including monocyclic and heterocyclic ethers bearing various functional groups.
- Igarashi, Takuya,Haito, Akira,Chatani, Naoto,Tobisu, Mamoru
-
p. 7475 - 7483
(2018/07/21)
-
- Dual C(sp3)?H Bond Functionalization of N-Heterocycles through Sequential Visible-Light Photocatalyzed Dehydrogenation/[2+2] Cycloaddition Reactions
-
Herein we describe a mild method for the dual C(sp3)?H bond functionalization of saturated nitrogen-containing heterocycles through a sequential visible-light photocatalyzed dehydrogenation/[2+2] cycloaddition procedure. As a complementary approach to the well-established use of iminium ion and α-amino radical intermediates, the elusive cyclic enamine intermediates were effectively generated by photoredox catalysis under mild conditions and efficiently captured by acetylene esters to form a wide array of bicyclic amino acid derivatives, thus enabling the simultaneous functionalization of two vicinal C(sp3)?H bonds.
- Xu, Guo-Qiang,Xu, Ji-Tao,Feng, Zhi-Tao,Liang, Hui,Wang, Zhu-Yin,Qin, Yong,Xu, Peng-Fei
-
supporting information
p. 5110 - 5114
(2018/03/27)
-
- Efficient nickel-catalysed: N -alkylation of amines with alcohols
-
The selective N-alkylation of amines with alcohols via the borrowing hydrogen strategy represents a prominent sustainable catalytic method, which produces water as the only by-product and is ideally suited for the catalytic transformation of widely available alcohol reaction partners that can be derived from renewable resources. Intensive research has been devoted to the development of novel catalysts that are mainly based on expensive noble metals. However, the availability of homogeneous or heterogeneous non-precious metal catalysts for this transformation is very limited. Herein we present a highly active and remarkably easy-to-prepare Ni based catalyst system for the selective N-alkylation of amines with alcohols, that is in situ generated from Ni(COD)2 and KOH under ligand-free conditions. This novel method is very efficient for the functionalization of aniline and derivatives with a wide range of aromatic and aliphatic alcohols as well as diols and exhibits excellent functional group tolerance including halides, benzodioxane and heteroaromatic groups. Several TEM measurements combined with elemental analysis were conducted in order to gain insight into the nature of the active catalyst and factors influencing reactivity.
- Afanasenko, Anastasiia,Elangovan, Saravanakumar,Stuart, Marc C. A.,Bonura, Giuseppe,Frusteri, Francesco,Barta, Katalin
-
p. 5498 - 5505
(2018/11/20)
-
- A new route to N-aromatic heterocycles from the hydrogenation of diesters in the presence of anilines
-
The hydrogenation of dicarboxylic acids and their esters in the presence of anilines provides a new synthesis of heterocycles. [Ru(acac)3] and 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos) gave good to excellent yields of the cyclic amines at 220 °C. When aqueous ammonia was used with dimethyl 1,6-hexadienoic acid, ?-caprolactam was obtained in good yield. A side reaction involving alkylation of the amine by methanol was suppressed by using diesters derived from longer chain and branched alcohols. Hydrogenation of optically pure diesters (dimethyl (R)-2-methylbutanedioate and dimethyl (S)-2-methylbutanedioate) with aniline afforded racemic 3-methyl-1-phenylpyrrolidine in 78% yield.
- Shi, Yiping,Kamer, Paul C. J.,Cole-Hamilton, David J.,Harvie, Michelle,Baxter, Emma F.,Lim, Kate J. C.,Pogorzelec, Peter
-
p. 6911 - 6917
(2017/10/05)
-
- Use of (cyclopentadienone)iron tricarbonyl complexes for c-n bond formation reactions between amines and alcohols
-
The application of a series of (cyclopentadienone)iron tricarbonyl complexes to "borrowing hydrogen" reactions between amines and alcohols was completed in order to assess their catalytic activity. The electronic variation of the aromatic groups flanking the C?O of the cyclopentadienone influenced the efficiency of the reactions; however, in other cases, the Kn?lker catalyst 1, containing trimethylsilyl groups flanking the cyclopentadienone ketone, gave the best results. In some cases, the change of the ratio of amine to alcohol improves the conversion significantly. The application of iron catalysts to the synthesis of a range of amines, including unsaturated amines, was investigated.
- Brown, Thomas J.,Cumbes, Madeleine,Diorazio, Louis J.,Clarkson, Guy J.,Wills, Martin
-
p. 10489 - 10503
(2018/05/31)
-
- Organonickel complexes encumbering bis-imidazolylidene carbene ligands: Synthesis, X-ray structure and catalytic insights on Buchwald-Hartwig amination reactions
-
New four coordinated homoleptic bis(diimidazolylidene)nickel(II) complexes (C1 & C2) were synthesized and characterized by elemental analysis, NMR (1H and13C) as well as ESI-Mass spectrometry. The molecular structure of the complex C1 was identified by means of single-crystal X-ray diffraction analysis, which revealed that the complexes possess a distorted square planar geometry with chelating bis(diimidazolylidene) NHC ligands and two non coordinating bromide counter ions in tetradentate C4fashion. A survey of their catalytic activity in Buchwald?Hartwig amination has been performed. The newly synthesized complexes also catalyzed the amination of aryl chlorides in the presence of KOtBu. Various aryl chlorides and amines can react smoothly to give the corresponding aminated products in moderate to high yields. The scope of the reaction encompasses electronically varied aryl chlorides and nitrogen-containing heteroaryl chlorides, including pyridine and quinoline derivatives. Both secondary and primary amines are well tolerated under the optimal reaction conditions.
- Nirmala, Muthukumaran,Saranya, Gandhi,Viswanathamurthi, Periasamy,Bertani, Roberta,Sgarbossa, Paolo,Malecki, Jan Grzegorz
-
supporting information
p. 1 - 10
(2017/01/09)
-
- Direct Acylation of C(sp3)-H Bonds Enabled by Nickel and Photoredox Catalysis
-
Using nickel and photoredox catalysis, the direct functionalization of C(sp3)-H bonds of N-aryl amines by acyl electrophiles is described. The method affords a diverse range of α-amino ketones at room temperature and is amenable to late-stage coupling of complex and biologically relevant groups. C(sp3)-H activation occurs by photoredox-mediated oxidation to generate α-amino radicals which are intercepted by nickel in catalytic C(sp3)-C coupling. The merger of these two modes of catalysis leverages nickel's unique properties in alkyl cross-coupling while avoiding limitations commonly associated with transition-metal-mediated C(sp3)-H activation, including requirements for chelating directing groups and high reaction temperatures. Teamwork: The direct functionalization of C(sp3)-H bonds of N-aryl amines by acyl electrophiles is achieved, thus affording a diverse range of α-amino ketones at room temperature. C(sp3)-H activation occurs by photoredox-mediated oxidation to generate α-amino radicals which are intercepted by nickel in catalytic C(sp3)-C coupling.
- Joe, Candice L.,Doyle, Abigail G.
-
supporting information
p. 4040 - 4043
(2016/03/19)
-
- Benzimidazolin-2-ylidene N-heterocyclic carbene complexes of ruthenium as a simple catalyst for the N-alkylation of amines using alcohols and diols
-
Simple air and moisture stable ruthenium complexes 1-3 and 3a were synthesized from readily available benzannulated N-heterocyclic carbene ligands (bimy = benzimidazolin-2-ylidene). These complexes were found to be efficient catalysts for the alkylation of amines using alcohols as alkylating agents. Catalysts 1, 2 and 3a gave excellent yields of up to 99% for the alkylation of various amines using benzylic and aliphatic alcohols at 130 °C for 18 h under solventless conditions. Catalyst 3a bearing both phosphine and carbene ligands gave excellent yields of up to 98% for the synthesis of heterocyclic amines by double alkylation of primary amines using linear diols. The practical utility of these catalysts was demonstrated for the synthesis of pharmaceutically important amines in a more environmentally benign way under solventless conditions.
- Shan, Siah Pei,Xiaoke, Xie,Gnanaprakasam, Boopathy,Dang, Tuan Thanh,Ramalingam, Balamurugan,Huynh, Han Vinh,Seayad, Abdul Majeed
-
p. 4434 - 4442
(2015/02/19)
-
- α-Cyanation of Aromatic Tertiary Amines using Ferricyanide as a Non-Toxic Cyanide Source
-
The reaction of aromatic tertiary amines with potassium ferricyanide directly provides the useful α-amino nitriles. The inexpensive iron complex functions both as an oxidant and as a cyanide source. The presence of molecular oxygen speeds up the reaction which can be performed in aqueous tert-butanol or even in ethanol-based mixtures like Tequila. While amine cyanations usually employ highly toxic cyanide sources, potassium ferricyanide is even less toxic than table salt. No expensive metal complexes are required as catalysts and the co-product of the cyanation, Prussian blue, has no known toxicity and is rather used as an antidote.
- Nauth, Alexander M.,Otto, Nicola,Opatz, Till
-
supporting information
p. 3424 - 3428
(2016/01/25)
-
- Internal and external stereoisomers of squaraine rotaxane endoperoxide: Synthesis, chemical differences, and structural revision
-
Photooxygenation of permanently interlocked squaraine rotaxanes with anthracene-containing macrocycles produces the corresponding squaraine rotaxane endoperoxides (SREPs) quantitatively. SREPs are stored at low temperature, and upon warming, they undergo
- Collins, Carleton G.,Lee, Joshua M.,Oliver, Allen G.,Wiest, Olaf,Smith, Bradley D.
-
p. 1120 - 1130
(2014/03/21)
-
- Nickel-catalyzed cross-coupling of aryltrimethylammonium triflates and amines
-
Nickel-catalyzed cross-coupling of aryltrimethylammonium triflates and amines was carried out under mild conditions. The reaction has a broad scope of substrates and can be performed by a one-pot procedure from an aryldimethylamine.
- Zhang, Xue-Qi,Wang, Zhong-Xia
-
p. 1448 - 1453
(2014/03/21)
-
- Copper-catalyzed electrophilic amination of organolithiums mediated by recoverable siloxane transfer agents
-
The development and validation of copper-catalyzed, electrophilic amination of aryl and heteroaryl organolithiums with N,N-dialkyl-O-benzoylhydroxylamines have been achieved exploiting recoverable siloxane transfer agents. Given the ready availability of organolithium compounds, the mild reaction conditions, the ease of product purification, and the ready recovery of the siloxane transfer agents, this transformation comprises a useful tactic to access diverse aryl and heteroaryl amines.
- Nguyen, Minh H.,Smith, Amos B.
-
supporting information
p. 4872 - 4875
(2013/10/08)
-
- N-heterocyclization of primary amines with dihalides using microreactors
-
(Chemical Equation Presented) A practical, rapid, and efficient reaction using microreactors for the direct N-alkylation from aniline derivatives and alkyl dihalides has been achieved in the presence of aqueous potassium carbonate at an elevated temperature. This improved synthetic methodology provides a straightforward microfluid approach to the synthesis of a variety of N-aryl azacycloalkanes. Copyright Taylor & Francis Group, LLC.
- He, Hongjie,Lin, Qi,Liu, Xiaofeng,Yang, Yongtai,Zhou, Yaming,Jia, Yu,Gao, Xiang
-
experimental part
p. 2512 - 2525
(2012/07/14)
-
- Heterogeneous bimetallic Pt-Sn/γ-Al2O3 catalyzed direct synthesis of diamines from N-alkylation of amines with diols through a borrowing hydrogen strategy
-
Direct synthesis of diamines has been efficiently realized from the N-alkylation of amines with diols by means of heterogeneous bimetallic Pt-Sn/γ-Al2O3 catalyst (0.5 wt % Pt, molar ratio Pt:Sn = 1:3) through a 'Borrowing Hydrogen' strategy under ligand-free conditions. The present methodology provides an environmentally benign route to diamines.
- Wang, Liandi,He, Wei,Wu, Kaikai,He, Songbo,Sun, Chenglin,Yu, Zhengkun
-
supporting information; experimental part
p. 7103 - 7107
(2012/01/05)
-
- Nickel-catalyzed amination of aryl Pivalates by the cleavage of aryl C-O bonds
-
(Figure Presented) Catalytic animation: The title reaction demonstrates the use of aryl carboxylates as suitable electrophilic coupling substrates in catalytic amination reactions. Nheterocyclic carbene ligands and NaOtBupromote the amination of aryl pivalates through the cleavage of normally unreactive aryl carbon-oxygen bonds (see scheme; cod = cyclooctadiene).
- Shimasaki, Toshiaki,Tobisu, Mamoru,Chatani, Naoto
-
supporting information; experimental part
p. 2929 - 2932
(2010/06/15)
-
- Platinum-catalyzed michael addition and cyclization of tertiary amines with nitroolefins by dehydrogenation of α,β-sp3 C-H bonds
-
A mild platinum-catalyzed oxidative dehydrogenation of α,β- C(sp3)-H bonds of tertiary amines in the presence of ambient oxygen is revealed, and the in situ formed enamines subsequently reacting with various nitroolefins resulted in the development of two one-pot synthetic protocols involving Michael addition-elimination and Michael addition-cyclization. By using different functionalized nitroolefins compatible with the current oxidative conditions, two types of structurally divergent products, trisubstituted enamines and chromano[2,3-b]piperidines, could be expediently accessed, respectively.
- Xia, Xiao-Feng,Shu, Xing-Zhong,Ji, Ke-Gong,Yang, Yan-Fang,Shaukat, Ali,Liu, Xue-Yuan,Liang, Yong-Min
-
supporting information; experimental part
p. 2893 - 2902
(2010/07/09)
-
- Aqueous-mediated N-alkylation of amines
-
Direct N-alkylation of primary amines to secondary/tertiary amines and of secondary amines to tertiary amines has been achieved in excellent yields by employing alkyl, benzylic and allylic halides in the presence of NaHCO 3 in an aqueous medium at an elevated temperature. Amines of different stereoelectronic nature react with ease with different halides. The selective formation of secondary amines and the formation of three different substituted tertiary amines are some of the interesting features of this methodology. Reaction in an aqueous medium, operationally convenient conditions, excellent yields and innocuous byproducts, and the absence of transition-metal catalysts, expensive bases, solid supports and the formation of undesired quaternary ammonium salts makes this method a green chemical process. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Singh, Chingakham B.,Kavala, Veerababurao,Samal, Akshaya K.,Patel, Bhisma K.
-
p. 1369 - 1377
(2008/09/17)
-
- Nickel(0)/dihydroimidazol-2-ylidene complex catalyzed coupling of aryl chlorides and amines
-
A general and simple nickel-catalyzed coupling of aryl chlorides and amines is reported. The scope and limitations of the coupling process using Ni(0), 1,3-bis(2,6-diisopropylphenyl)dihydroimidazol-2-ylidene, and NaO-t-Bu as base were investigated. Secondary cyclic and acyclic amines and anilines provided the arylamine coupling products in good to excellent yields. Compared to palladium-catalyzed aminations, this procedure offers an alternative route to N-substituted anilines starting from readily available aryl chlorides.
- Desmarets, Christophe,Schneider, Raphael,Fort, Yves
-
p. 3029 - 3036
(2007/10/03)
-
- Ruthenium-complex-catalyzed N-(Cyclo)alkylation of aromatic amines with diols. Selective synthesis of N-(ω-hydroxyalkyl)anilines of type PhNH(CH2)(n)OH and of some bioactive arylpiperazines
-
A new class of well-defined neutral mono-, and dicationic ruthenium(II) complexes containing a neutral terdentate donor system [C5H3N(CH2E)2- 2,6] (E = PPh2 (PNP) or NME2 (NN'N) has been found effective as catalyst precursor in N-(cyclo)alkylation reactions of aromatic amines with diols Y(CH2CH2OH)2 (Y = CH2, NR). With these catalysts, N-phenylpiperidine is synthesized from aniline and 1,5-pentanediol in 85% yield (at 180 °C for 24 h in 1.4-dioxane). With neutral RuCl2(NN'N)-(PPh3) as a catalyst precursor, aniline can be selectively N-monoalkylated with diols of the type HO(CH2)(n)OH (n = 4-6, 10) to give N-(n-hydroxyalkyl)anilines in 40-75 yield. To our knowledge, this represents the first useful catalytic route to this type of compounds. The new catalysts can also be used in the synthesis of arylpiperazines. For example, N-phenyl-N'-methylpiperazine is obtained from aniline and MeN(CH2CH2OH)2 in yields up to 34%. N- [m(Trifluoromethyl)phenyl]-N'-methylpiperazine, TFMPMP, is successfully produced from m-(trifluoromethyl)aniline and MeN-(CH2CH2OH)2 in 44% yield using monocationic [RuOTf(NN'N)(PPh3)]OTf as the catalyst precursor. A mechanism for the N-(cyclo)alkylation reaction is proposed.
- Abbenhuis,Boersma,Van Koten
-
p. 4282 - 4290
(2007/10/03)
-
- N-ALKYLATION AND N-ARYLATION OF ANILINES STARTING FROM A MILD N-Mg REAGENT: ITS ACTIVATION CAUSING THE 'N-C' COUPLING TO EXTEND THE UNIFIED STRUCTURE-REACTIVITY RELATIONSHIP
-
New N-alkylation and N-arylation procedures starting from anilinomagnesium (ArNHMgBr) are reported.For N-alkylation with alkyl bromides, addition of hexamethylphosphoramide to an ArNHMgBr solution in tetrahydrofuran (THF) is effective.After heating at 55 deg C, N-monoalkylation product was obtained in 60-90percent yield, slight dialkylation taking place.The combined use of aryliminodimagnesium with α,ω-dibromoalkanes led to N-arylazacycloalkanes.For N-arylation with iodobenzene, replacement of THF with pyridine and additional use of copper(I) iodide are effective.After heating at 115 deg C with iodobenzene, mono- and diarylation products were obtained, the former being predominant.The combined use of ArNHMgBr and N,N,N',N'-tetramethylethylenediamine as the ligand of copper species is effective for elimination of diarylation and other undesired products, and leads to diarylamines in excellent yield.The method is of advantage over the conventional Ullmann and Chapman methods.The polar solvents and copper salt are effective additives for inducing 'inert combinations' of ArNHMgBr or ArN(MgBr)2 with alkyl and aryl halides into N-C coupling, to extend the unified view proposed for the reactivity of magnesium reagents.The difference in the roles of N-Mg and N-Cu species is discussed.
- Matsuo, Koji,Shichida, Yoshiaki,Nishida, Hiroshi,Nakata, Satsuki,Okubo, Masao
-
-
- gem-cyclodialkylation A facile synthetic route to N-substituted heterocycles
-
N-alkylated and N-arylated pyrroles, pyrrolidines, and piperidines are synthesized in high yield by the reaction between cyclic ethers and primary amines over a heterogeneous titania catalyst.
- Hargis, Duane C.,Shubkin, Ronald L.
-
p. 2991 - 2994
(2007/10/02)
-
- A versatile method for the N,N-dialkylation of aromatic amines via Grignard reactions on N,N-bis(benzotriazolylmethyl)arylamines
-
Grignard reactions of N,N-bis(benzotriazolylmethyl)arylamines afford the corresponding N,N-dialkylarylamines in high yields.Electron-releasing substituents on the aryl ring facilitate the reaction.Arylamines are N,N-dialkylated with two different alkyl groups by a stepwise procedure: N-benzotriazolylmethylation of an amine followed by a Grignard reaction to introduce the first alkyl group, and repetition of the same procedure to introduce the second alkyl group.Grignard reagents derived from 1,4-dihalobutane, upon reaction with N,N-bis(benzotriazolylmethyl)arylamines, give the corresponding N-aryl-hexahydroazepines together with acyclic products.
- Katritzky, Alan R.,Rachwal, Stanislaw,Wu, Jing
-
p. 456 - 463
(2007/10/02)
-
- A New and Convenient Synthesis of N-Substituted Perhydroazepines from Adipaldehyde and Primary Amines with Tetracarbonylhydridoferrate, HFe(CO)4-, as a Selective Reducing Agent
-
Ethanolic tetracarbonylhydridoferrate combined with adipaldehyde is very efficient for the selective transformation of an amino group into perhydroazepine.A large variety of both aliphatic and aromatic amines react with adipaldehyde in the presence of tetracarbonylhydridoferrate at room temperature and carbon monoxide to give the corresponding N-alkyl- and N-arylperhydroazepines in good to excellent yields.
- Shim, Sang Chul,Doh, Chil Hoon,Kim, Tae Jeong,Lee, Hak Ki,Kim, Ki Doo
-
p. 1383 - 1385
(2007/10/02)
-
- SYNTHESIS OF STERICALLY HINDERED 1-ARYLPYRROLIDINES AND 1-ARYLPIPERIDINES BY CONDENSATION OF PRIMARY AROMATIC AMINES WITH CYCLIC ETHERS OR DIOLS
-
A variety of 1-(o-alkylphenyl)- and 1-(o-o'-dialkylphenyl)-pyrrolidines and -piperidines were prepared by the gas phase alumina mediated condensation of tetrahydrofuran (THF), tetrahydropyran (THP) or the corresponding diols with primary aromatic amines in fair to high yield.This methodology can also be used for the synthesis of 1-phenylhexahydroazepine from aniline.A mechanistic interpretation of the catalytic action of alumina is presented.
- Walkup, Robert E.,Searles, Scott
-
p. 101 - 106
(2007/10/02)
-