共查询到19条相似文献,搜索用时 62 毫秒
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手性1,2-二氢吡啶化合物是重要的手性砌块, 可通过还原或环加成反应来方便构建药物分子中十分重要的手性含氮杂环化合物如哌啶等, 因此其高效合成对于新药研发具有重要的研究意义. 利用手性源和手性辅基诱导的策略需要使用化学计量的手性试剂, 发展不对称催化的方法来合成结构多样性的手性1,2-二氢吡啶化合物无疑十分重要. 自2004年报道首例对活化吡啶的不对称C2位亲核加成反应以来, 该策略被成功用于发展合成C2位芳基、烷基、炔基等取代的手性1,2-二氢吡啶化合物的不对称催化新方法. 最近, 一种新的基于亚胺不对称转化的串联反应策略也被设计开发用于多样性合成这类手性含氮杂环化合物. 本综述概述了相关研究进展, 并介绍了相关研究难点和未来的发展空间. 相似文献
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利用手性元途径来合成光学活性化合物近年来受到特别重视。在利用天然易得的糖、氨基酸和萜类化合物来合成各种手性元上,发展了不少十分有价值的策略[1]。(+)二氢香芹酮分子中有两个手性碳,是一种手性合成常用的原料。我们曾报道了由(+)二氢香芹酮合成(+)1... 相似文献
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Jinshui Chen Dr. Norito Takenaka Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(30):7268-7276
Optically active chiral alkyl chlorides are valuable compounds because of their bioactivity and versatile synthetic utility. Accordingly, the ring opening of epoxides with a chloride nucleophile stands as an important goal in asymmetric catalysis. We describe herein recent advances in the design and development of chiral pyridine N‐oxide catalysts for the enantioselective synthesis of chlorohydrins. 相似文献
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Sadhukhan A Khan NU Roy T Kureshy RI Abdi SH Bajaj HC 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(17):5256-5260
A chiral cobalt(III) complex (1e) was synthesized by the interaction of cobalt(II) acetate and ferrocenium hexafluorophosphate with a chiral dinuclear macrocyclic salen ligand that was derived from 1R,2R-(-)-1,2-diaminocyclohexane with trigol bis-aldehyde. A variety of epoxides and glycidyl ethers were suitable substrates for the reaction with water in the presence of chiral macrocyclic salen complex 1e at room temperature to afford chiral epoxides and diols by hydrolytic kinetic resolution (HKR). Excellent yields (47% with respect to the epoxides, 53% with respect to the diols) and high enantioselectivity (ee>99% for the epoxides, up to 96% for the diols) were achieved in 2.5-16 h. The Co(III) macrocyclic salen complex (1e) maintained its performance on a multigram scale and was expediently recycled a number of times. We further extended our study of chiral epoxides that were synthesized by using HKR to the synthesis of chiral drug molecules (R)-mexiletine and (S)-propranolol. 相似文献
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Arghya Sadhukhan Dr. Noor‐ul H. Khan Tamal Roy Dr. Rukhsana I. Kureshy Dr. Sayed H. R. Abdi Dr. Hari C. Bajaj 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(17):5256-5260
A chiral cobalt(III) complex ( 1 e ) was synthesized by the interaction of cobalt(II) acetate and ferrocenium hexafluorophosphate with a chiral dinuclear macrocyclic salen ligand that was derived from 1R,2R‐(?)‐1,2‐diaminocyclohexane with trigol bis‐aldehyde. A variety of epoxides and glycidyl ethers were suitable substrates for the reaction with water in the presence of chiral macrocyclic salen complex 1 e at room temperature to afford chiral epoxides and diols by hydrolytic kinetic resolution (HKR). Excellent yields (47 % with respect to the epoxides, 53 % with respect to the diols) and high enantioselectivity (ee>99 % for the epoxides, up to 96 % for the diols) were achieved in 2.5–16 h. The CoIII macrocyclic salen complex ( 1 e ) maintained its performance on a multigram scale and was expediently recycled a number of times. We further extended our study of chiral epoxides that were synthesized by using HKR to the synthesis of chiral drug molecules (R)‐mexiletine and (S)‐propranolol. 相似文献
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Pineschi M Del Moro F Crotti P Di Bussolo V Macchia F 《The Journal of organic chemistry》2004,69(6):2099-2105
A novel regiodivergent kinetic resolution of a series of allylic epoxides with alkylzinc reagents is described. Results demonstrate the potential of chiral copper-phosphoramidite catalysts for enantiomer differentiation of allylic epoxides, allowing a chiral catalyst-stereoregulated synthesis of cyclic allylic and homoallylic alcohols with high optical purities. 相似文献
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《Tetrahedron: Asymmetry》2006,17(10):1465-1492
Enantioselective organocatalytic processes have reached maturity in recent years with an impressive number of applications now available. The application of these advantageous methodologies to the construction of chiral α-hetereofunctionalised carbonyl compounds allows us to obtain important chiral building blocks, such as α-amino acids, α-amino alcohols, aziridines, epoxides, 1,2-diols and α-sulfenylated, selenenylated and halogenated carbonyl derivatives. Proline, imidazolidinone derivatives, cinchona alkaloids and their ammonium salts, as well as Brønsted acid derivatives, have been used as chiral catalysts for these purposes. A survey of contributions in this field will be discussed throughout this review. 相似文献
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近年来手性沙美特罗的合成方法有微生物催化、不对称氢化、CBS(Corey-Bakshi-Shibata)还原反应及不对称Henry反应、手性(Salen)Co试剂催化的HKR(末端环氧不对称水解动力学)拆分反应等。对这些方法进行比较,结果表明,不对称催化合成由于其反应收率高、反应产物光学纯度高、操作容易控制,在目前手性药物的合成中处于主导地位。此外酶催化不对称合成、手性辅基诱导的对映选择性合成等方法也是有效的途径。 相似文献
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Direct conversion of epoxides to aziridines was achieved with guanidines as a nitrogen source. Stereochemical inversion at the chiral centers of epoxides was observed without loss of optical purity. 相似文献