enantioenriched tertiaryalcohols in pharmaceutical chemistry, efficient and green strategies for their synthesis are highly sought after. Here, we report a simple synthesis of the elusive chiral tertiaryalcohols. A cytochrome P450 monooxygenase called P450PL2 was developed to enable chiral tertiaryalcohols by the benzylic CH bonds asymmetric hydroxylation of the racemic tertiary carbon substrates
鉴于对映体丰富的叔醇在药物化学中的重要性和有益特性,高效且绿色的合成策略受到高度追捧。在这里,我们报告了难以捉摸的手性叔醇的简单合成。开发了一种称为 P450 PL2的细胞色素 P450 单加氧酶,通过外消旋叔碳底物的苄基 C H 键不对称羟基化来生成手性叔醇。这种 P450 催化方案提供了各种手性叔醇,具有意想不到的官能团耐受性和优异的对映选择性(高达 >99% ee)。该方法反应温和,采用分子氧作为氧化剂,避免了预氧功能化底物的使用。进行了初步的分子动力学模拟研究,以揭示 P450 PL2催化过程中底物异常选择性羟基化的可能原因。
First catalytic enantioselective synthesis of the cocaine abuse therapeutic agent (S)-(+)-1-(4-{2-[bis(4-fluorophenyl)methoxy]ethyl}piperazin-1-yl)-2-phenyl-2-propanol
作者:Vicente J. Forrat、Diego J. Ramón、Miguel Yus
DOI:10.1016/j.tetasy.2006.12.028
日期:2007.2
(S)-(+)-1-(4-2-[Bis(4-fluorophenyl)methoxy]ethyl} piperazin-1-yl)-2-phenyl-2-propanol, which is a promising candidate as a cocaine abuse therapeutic agent, is prepared in several steps. The key asymmetric step is the catalytic enantioselective addition of dimethylzinc to either 2-chloro or 2-bromoacetophenone catalyzed by the use of different chiral isoborneolsulfonamide ligands in the presence of titanium tetraisopropoxide. The synthesis of a new isoborneolsulfonamide ligand bearing a trifluromethyl. substituent and its use in this addition is also presented. (c) 2007 Elsevier Ltd. All rights reserved.
Oxidation of olefins by palladium(II). 18. Effect of reaction conditions, substrate structure and chiral ligand on the bimetallic palladium(II) catalyzed asymmetric chlorohydrin synthesis
作者:Arab K El-Qisairi、Hanan A Qaseer、Patrick M Henry
DOI:10.1016/s0022-328x(02)01580-2
日期:2002.8
The effect of electronic factors, solvent composition, identity of the chiral bidentate, and olefinstructure on the yields and enantioselectivities of the asymmetric chlorohydrin synthesis were investigated. Electronic effects on the chlorohydrin reaction were tested by oxidation of phenyl allyl ether p-substituted by H, Cl, CH3O and CN. All species gave same similar yields and enantioselectivities