Stereoselective chemoenzymatic synthesis of both enantiomers of protected 4-amino-2-pentanone
摘要:
An acetal protected 4-amino-2-pentanone was synthesised by two different routes in 10 and seven steps, respectively, the key step being a microbiological reduction. Both enantiomers of the amine were obtained enantiomerically pure. (C) 1999 Elsevier Science Ltd. All rights reserved.
Stereoselective chemoenzymatic synthesis of both enantiomers of protected 4-amino-2-pentanone
摘要:
An acetal protected 4-amino-2-pentanone was synthesised by two different routes in 10 and seven steps, respectively, the key step being a microbiological reduction. Both enantiomers of the amine were obtained enantiomerically pure. (C) 1999 Elsevier Science Ltd. All rights reserved.
While the first total synthesis of modiolide A (1a), a 10-membered ring lactone with a marine-origin was achieved, an important chiral building block for constructing the chirality at C-4 in 1a, (S)-6-[(4-methoxybenzyl)oxy]-1-trimethylsilyl-1-hexyn-3-ol (3a) was obtained in as high as 96.1% ee. Asymmetric reduction of a silylated propargyl ketone (5) mediated by whole-cell of Pichia minuta IAM 12215
The preparation of (S)-1-(1,3-dithian-2-yl)-2-hydroxypropane and its transformation into (S,S)-(+)-grahamimycin A1, through intramolecular pinacolic coupling of dialdehyde , are described.
An asymmetric, catalytic, and direct self-aldol reaction of acetaldehyde was catalyzed by diarylprolinol in NMP, affording the trimer acetal, which was generated by the reaction of the self-aldol product with another acetaldehyde molecule in a moderate yield with good enantioselectivity. Acetal is the synthetic equivalent of the self-aldol product, which can be converted into other synthetically useful
motif and a novel set of homochiral linkers has been synthesized. Starting from amino acids available from the chiral pool a synthesis procedure was established that allows a straightforward, multigram scale synthesis of homochiral linkers in 4–5 steps. These linkers carry substituents that have been proven useful in stereoselective organic chemistry, such as the Evans auxiliary or chiral amino alcohols
基于铜桨轮基序和一组新的同手性连接基,已经合成了一个新的等网状金属-有机骨架系列,称为UHM-25(UHM:汉堡材料大学)。从手性库中可用的氨基酸开始,建立了合成程序,该程序允许在4-5个步骤中直接,数克规模的同手性连接体合成。这些接头带有已被证明可用于立体选择性有机化学的取代基,例如伊文思助剂或手性氨基醇。所得的MOF仅在氨基酸原料提供的手性部分上有所不同。UHM-25的结构由Cu 2的立方八面体笼组成通过连接子的间苯二甲酸酯部分连接的桨轮图案。这些笼通过连接子的弯曲骨架连接在一起,从而形成原始的立方排列,从而产生了稀有的下层(3,4)-c双齿净ucp。UHM-25系列的MOF的表面积高达S BET = 1900 m 2 / g。具有优良转化率的合成后修饰反应证实了手性基团的可及性。此外,带有丙醇功能的UHM-25-Pro被用于乙醛的自定向对映选择性醇醛加成中,证明了UHM-25系列在多相,立体选择性催化方面的潜力。
Verfahren zur Herstellung von optisch aktiven sekundären Alkoholen aus Ketonen unter Verwendung einer adsorbierten Carbonylreduktase-Aktivität
申请人:Wacker Chemie AG
公开号:EP1832658A1
公开(公告)日:2007-09-12
Verfahren zur Herstellung eines chiralen sekundären Alkohols bei dem eine Biotransformationszusammensetzung, enthaltend ein Keton der Formel (I),
wobei R1 und R2 verschieden sind und jeweils organischer Rest bedeuten, eine Oxidoreduktase und ein Cosubstrat, zur Reaktion gebracht wird, wobei ein chiraler sekundärer Alkohol entsteht, dadurch gekennzeichnet, dass die Biotransformationszusammensetzung ein Adsorbens enthält, welches mit der Oxidoreduktase assoziiert und welches nach dem Ende der Reaktion von der Biotransformationszusammensetzung abgetrennt wird.