- Vanadium Imido NHC Complexes for Ring-Closing Olefin Metathesis Reactions
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Vanadium bis-phosphine imido and oxo chloride alkylidenes have been extensively applied in the ring-closing metathesis of various acyclic olefins. However, their reactions involving ethylene have shown limited productivity due to rapid decomposition. The
- Belov, Dmitry S.,Bukhryakov, Konstantin V.,Fenoll, Didac A.,Rue, Kelly L.,Solans-Monfort, Xavier,Tejeda, Gabriela,Tsay, Charlene
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supporting information
p. 361 - 365
(2022/02/23)
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- Preparation method of medical intermediate N-BOC-3-pyrroline
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The invention discloses a preparation method of a medical intermediate N-BOC-3-pyrroline. The method comprises the following steps: adding a proper amount of benzylamine, 3-bromopropylene, dichloromethane and an alkaline reagent into a reaction bottle for reaction to obtain an enamine compound; dissolving the enamine compound in dichloromethane, adding a catalyst (Grubbs first generation) for reaction, adding anhydrous sodium sulfate after adding water for layering, and performing suction filtration to obtain mother liquor; adding 1-chloroethyl chloroformate and methanol into the mother liquor, debenzylating to obtain pink solid, adding petroleum ether into the pink solid, pulping, and carrying out suction filtration to obtain 3-pyrroline hydrochloride; and re-dissolving the 3-pyrroline hydrochloride with water, adding an alkaline solution of NaHCO3 and (BOC)2O, stirring and reacting, extracting after the reaction is finished, separating out an organic phase, and drying to obtain a finished product of N-BOC-3-pyrroline. The method is low in raw material cost, simple in process step, high in yield, small in pollution, high in product purity and suitable for industrial production.
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Paragraph 0065; 0067; 0069; 0071; 0073; 0075
(2021/07/31)
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- Preparation method of medical intermediate N-benzyl-3-pyrroline
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The invention discloses a preparation method of a medical intermediate N-benzyl-3-pyrroline. The method comprises the following steps: adding a proper amount of benzylamine, maleic anhydride and a reaction medium into a reaction flask, and stirring for reaction to obtain a diamide compound; and dissolving a diamide compound in tetrahydrofuran, dropwise adding a proper amount of 70% red aluminum solution, and reducing the diamide compound to obtain N-benzyl-3-pyrroline; The method is low in raw material cost, simple in process step, high in yield, small in pollution, high in product purity and suitable for industrial production.
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Paragraph 0039; 0042; 0044-0045; 0047-0048; 0050
(2021/08/28)
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- Ring-Closing Olefin Metathesis Catalyzed by Well-Defined Vanadium Alkylidene Complexes
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Vanadium-based catalysts have shown activity and selectivity in ring-opening metathesis polymerization of strained cyclic olefins comparable to those of Ru, Mo, and W catalysts. However, the application of V alkylidenes in routine organic synthesis is limited. Here, we present the first example of ring-closing olefin metathesis catalyzed by well-defined V chloride alkylidene phosphine complexes. The developed catalysts exhibit tolerance to various functional groups, such as an ether, an ester, a tertiary amide, a tertiary amine, and a sulfonamide. The size and electron-donating properties of the imido group and the phosphine play a crucial role in the stability of active intermediates. Reactions with ethylene and olefins suggest that both β-hydride elimination of the metallacyclobutene and bimolecular decomposition are responsible for catalyst degradation.
- Belov, Dmitry S.,Tejeda, Gabriela,Tsay, Charlene,Bukhryakov, Konstantin V.
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supporting information
p. 4578 - 4582
(2021/02/11)
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- Molybdenum Benzylidyne Complexes for Olefin Metathesis Reactions
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The molybdenum benzylidynes [ArCMo(OC(CF3)2CH3)3(1,2-dimethoxyethane)], where Ar = Ph (2a), p-(OCH3)C6H4 (2b), p-(CF3)C6H4 (2c), p-(NO2)C6H4 (2d), or 4-(NO2)-3-(CF3)C6H3 (2e), and [p-(NO2)C6H4CMo(OC(CF3)2CH3)3] (2f) catalyze the ring-closing metathesis (RCM) reaction of diallyl N-tosylamide (3) to produce 1-tosyl-2,5-dihydro-1H-pyrrole (4) and ethylene. The scope of RCM catalytic activity of 2e, cross-metathesis of 1-hexene, and ring-opening metathesis polymerization of cyclooctene were explored. The X-ray crystal structure of 2e was determined. Variable-temperature 1H NMR spectra revealed the formation of intermediates during the reaction of 3 with 2f and the reforming of 2f after completion of the reaction. The use of 13C-labeled Mo benzylidyne did not show transfer of the carbon atom next to Mo to any of the products.
- Acosta, Carlos M.,Bukhryakov, Konstantin V.,Chuprun, Sergey,Mathivathanan, Logesh
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supporting information
p. 3453 - 3457
(2020/11/02)
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- Reductive C-O, C-N, and C-S Cleavage by a Zirconium Catalyzed Hydrometalation/β-Elimination Approach
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A zirconium catalyzed reductive cleavage of Csp3 and Csp2 carbon-heteroatom bonds is reported that makes use of a tethered alkene functionality as a traceless directing group. The reaction is successfully demonstrated on C-O, C-N, and C-S bonds and proposed to proceed via a hydrozirconation/β-heteroatom elimination sequence of an in situ formed zirconium hydride catalyst. The positional isomerization of the catalyst further enables the cleavage of homoallylic ethers and the removal of terminal allyl and propargyl groups.
- Matt, Christof,K?lblin, Frederic,Streuff, Jan
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supporting information
p. 6983 - 6988
(2019/09/09)
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- Highly Selective Carboxylative Cyclization of Allenylmethylamines with Carbon Dioxide Using N-Heterocyclic Carbene-Silver(I) Catalysts
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Silver(I) carboxylate complexes promote the carboxylative cyclization of allenylmethylamines to afford 5-alkenyl-1,3-oxazolidin-2-ones in 2-propanol. The use of an N-heterocyclic carbene ligand (IPr) under pressurized CO2 is effective in suppre
- Yamashita, Kyohei,Hase, Shun,Kayaki, Yoshihito,Ikariya, Takao
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supporting information
p. 2334 - 2337
(2015/05/27)
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- An atom efficient route to N-aryl and N-alkyl pyrrolines by transition metal catalysis
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The synthesis of N-aryl, N-tosyl, and N-alkyl pyrrolines from allyl alcohols and amines has been developed. The reaction sequence includes a palladium-catalyzed allylation step in which non-manipulated allyl alcohol is used to generate the diallylated amine in good to excellent yield. An excess of allyl alcohol was necessary for efficient diallylation of the amine, where the excess alcohol could be recycled three times. For aryl and tosyl amines, Pd[P(OPh)3]4 was used and for benzyl and alkyl amines a catalytic system comprising Pd(OAc)2, PnBu3, and BEt3 was used. Both the electronic properties and the steric influence of the amine affected the efficiency of the allylation. The isolated diallylated amines were transformed into their corresponding pyrrolines by ring-closing metathesis catalyzed by (H2IMes)(PCy3)Cl 2RuCHPh in good to excellent yield. A one-pot reaction was developed in which aniline was transformed into the corresponding pyrroline without isolating the diallylated intermediate. This one-pot reaction was successfully scaled-up to 1 mL of aniline in which the N-phenyl pyrroline was isolated in 95% yield. The versatility of the reaction in which 3-methyl-1-phenyl pyrroline was prepared in two-steps was demonstrated.
- Sawadjoon, Supaporn,Samec, Joseph S. M.
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experimental part
p. 2548 - 2554
(2011/05/04)
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- Practical synthetic process for enantiopure 1-benzyl-3-hydroxypyrrolidine
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The synthesis of (S)-1-benzyl-3-hydroxypyrrolidine (S)-5 comprised the asymmetric hydroboration of 1-benzyl-3-pyrroline 4, followed by oxidation and chiral purification via diastereomeric salt formation. The asymmetric borane reagent was generated 'in situ' from NaBH4, BF3-OEt2, and (+)-α-pinene 1 (85% ee) and reacted with 4, prepared from cis-1,4-butenediol 3, to give crude product (S)-5. The following chiral purification via diastereomeric salt formation proceeded to afford (S)-5 with >99% ee. The optimized process was successfully scaled up to an industrial scale to produce a 252 kg batch of (S)-5.
- Morimoto, Masao,Sakai, Kenichi
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p. 1464 - 1468
(2008/12/20)
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- Production process for bicyclic tetrahydropyrrole compounds
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The present invention relates to a process using the Pauson-Khand Reaction to produce substituted bicyclic tetrahydropyrrole compounds of general formula (I),
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Page/Page column 14
(2008/06/13)
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- Substituted 3-Amino-4-hydroxy pyrrolidines compounds, their preparation and use as medicaments
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The present invention relates to substituted pyrrolidine compounds of general formula (I), methods for their preparation, medicaments comprising these compounds as well as their use for the preparation of a medicament for the treatment of humans and animal.
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Page/Page column 88
(2008/06/13)
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- Bicyclic tetrahydropyrrole compounds
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The present invention relates to substituted bicyclic tetrahydropyrrole compounds of general formula (I), methods for their preparation, medicaments comprising these compounds as well their use in the manufacture of a medicament for the treatment of humans and animals.
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Page/Page column 18
(2010/11/28)
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- Room temperature ionic liquids: New solvents for Schrock's catalyst and removal using polydimethylsiloxane membranes
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A room temperature ionic liquid was used as the solvent for metathesis reactions with the Schrock catalyst and a new method to facilitate separation between small molecules and ionic liquids using polydimethylsiloxane thimbles is reported. The Royal Socie
- Miller II, A. Lee,Bowden, Ned B.
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p. 2051 - 2053
(2008/02/09)
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- NOVEL ALKYNE COMPOUNDS EXHIBITING AN MCH ANTAGONISTIC EFFECT AND DRUGS CONTAINING SAID COMPOUNDS
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The invention relates to an alkyne compound of general formula (I) in which A, B, W, X, Y, Z, R and R groups and residuals have the meanings given in claim 1. Drugs containing at least one type of inventive alkyne are also disclosed. The inventive drugs exhibiting an MCH-receptor antagonistic activity are suitable for treating metabolic disturbances and/or eating disorders, in particular adiposity, bulimia, anorexia, hyperphagia and diabetes.
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Page/Page column 64
(2008/06/13)
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- Alkyne compounds with MCH antagonistic activity and medicaments comprising these compounds
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The present invention relates to alkyne compounds of general formula I wherein the groups and radicals A, B, W, X, Y, Z, R1 and R2 have the meanings given in claim 1. Moreover the invention relates to pharmaceutical compositions containing at least one alkyne according to the invention. By virtue of their MCH-receptor antagonistic activity the pharmaceutical compositions according to the invention are suitable for the treatment of metabolic disorders and/or eating disorders, particularly obesity and diabetes.
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Page/Page column 25-26
(2010/02/14)
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- NOVEL ALKYNE COMPOUNDS WITH AN MCH-ANTAGONISTIC ACTION AND MEDICAMENTS CONTAINING SAID COMPOUNDS
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The invention relates to alkyne compounds of general formula (I), in which the groups and radicals A, B, W, X, Y, Z, R1 and R2 are defined as cited in claim 1. The invention also relates to medicaments containing at least one inventive alkyne. As a result of the antagonistic action against the MCH-receptor, the inventive medicaments are suitable for treating metabolic disorders and/or eating disorders, in particular adiposity and diabetes.
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Page/Page column 67
(2010/02/14)
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- Alkyne compounds with MCH antagonistic activity and medicaments comprising these compounds
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Alkyne compounds of formula I wherein A, B, W, X, Y, Z, R1, and R2 have the meanings given herein, which have MCH-receptor antagonistic activity and are useful for preparing pharmaceutical compositions for the treatment of metabolic disorders and/or eating disorders, particularly obesity and diabetes.
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Page/Page column 24
(2010/02/14)
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- Lewis acid assisted ring-closing metathesis of chiral diallylamines: An efficient approach to enantiopure pyrrolidine derivatives
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(Chemical Equation Presented) Lewis acid assisted ring-closing olefin metathesis (RCM) of chiral diallylamines, using the second generation RCM ruthenium-based catalyst, leads to enantiopure pyrrolidine derivatives in 79-93% yields under very mild conditi
- Yang, Qian,Xiao, Wen-Jing,Yu, Zhengkun
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p. 871 - 874
(2007/10/03)
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- Model studies towards kainic acid
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A novel photochemical approach to the kainoid ring system is presented alongside model studies to demonstrate its feasibility.
- Greenwood,Parsons
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p. 167 - 169
(2007/10/03)
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- Method of producing pyrrolidine derivatives
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A method for producing pyrrolidine derivatives such as 3,4-epoxypyrrolodines, 3-pyrrolidols and the like, by oxidizing 3-pyrrolines with at least one peroxide in the presence of at least one acid is disclosed. The 3-pyrrolines are produced by deriving cis-2-butene compounds from cis-2-butene-1,4-diols and performing a cyclization between the cis-2-butene derivatives and at least one primary amine. The method may be performed as a one-pot synthesis and may be performed as a continuous reaction.
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- A convenient one-pot synthesis of N-aryl-3-pyrrolines
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N-propargylanilines under one-pot homologation conditions, undergo an in situ cyclisation catalysed by Cu(I) to yield 3-pyrrolines in good yield.
- Jayaprakash, Karamil,Venkatachalam, Chittoor S.,Balasubramanian, Kalpattu K.
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p. 6493 - 6496
(2007/10/03)
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- Catalytic ring-closing olefin metathesis of sulfur-containing species: Heteroatom and other effects
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This paper describes studies of the ring-closing metathesis of dialkyl sulfides and disulfides catalyzed by molybdenum and ruthenium alkylidenes. In general, the highest yields of ring-closed products were obtained using the molybdenum catalysts. Product yields were also strongly influenced by the substitution pattern about the double bonds: the yield of ring-closed products was found to decrease as the degree of substitution increased. These effects and other heteroatom effects are discussed.
- Shon, Young-Seok,Lee, T. Randall
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p. 1283 - 1286
(2007/10/03)
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- Novel 2-amino-1,4-dihydropyridine calcium antagonists. II. Synthesis and antihypertensive effects of 2-amino-1,4-dihydropyridine derivatives having N,N-dialkylaminoalkoxycarbonyl groups at 3- and/or 5-positions
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Novel 2-amino-1,4-dihydropyridine derivatives I, which contain N,N-dialkylaminoalkoxycarbonyl groups at the 3- and/or 5-position, were synthesized and their antihypertensive effects were evaluated in spontaneously hypertensive rats. Remarkably prolonged duration of antihypertensive action was observed when a tertiary amino group was introduced into either the 3- or 5-ester side-chain of the 1,4-dihydropyridine ring. In particular, the compounds containing cyclic amino moieties at the 3-position showed greater potency than those with acyclic amino moieties. Chemical modification studies indicated that the two ester side-chains of 1,4-dihydropyridine at the 3- and 5-position might function in a different manner in relation to the antihypertensive activities. 3-(1-Benzhydrylazetidin-3-yl) 5-isopropyl 2-amino-1,4-dihydro-6-methyl-4-(3-nitrophenyl)-3,5-pyridine-dicarboxyl ate, I-43 (CS-905), exhibited potent and long-lasting antihypertensive effects with gradual onset of action, and is a promising candidate as an antihypertensive drug.
- Kobayashi,Inoue,Nishino,Fujihara,Oizumi,Kimura
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p. 797 - 817
(2007/10/02)
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- A Facile Synthesis of 3-Pyrrolines
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N-Substituted 3-pyrrolines were conveniently synthesized in high yield by the treatment of primary amines with cis-2-butene-1,4-diol dimesylate, which was generated from cis-1,4-butenediol.
- Ding, Zhaozhong,Tufariello, Joseph J.
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p. 227 - 230
(2007/10/02)
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- Reactions of Tertiary Allylamines with Dimethyl Acetylenedicarboxylate
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The reaction of some tertiary allylamines with dimethyl acetylenedicarboxylate in acetonitrile results in the formation of 1:1 adducts via rearrangement of the allyl group from nitrogen to carbon.
- Kandeel, Kamal A.,Vernon, John M.
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p. 2023 - 2026
(2007/10/02)
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- SYNTHETIC ROUTES TO 3-PYRROLIDINOL
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Short, convenient routes to 3-pyrrolidinol are described.
- Nemia, Mergaret M. Bowers,Lee, Jessie,Joullie, Madeleine M.
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p. 1117 - 1124
(2007/10/02)
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