在In / CuI / I 2或In / AgI / I 2系统存在下,使用未活化的烷基卤化物在水中进行醛的Barbier-Grignard型烷基化反应(包括脂肪族)的有效方法。该反应在水中比在有机溶剂中更有效地进行。In,CuI或AgI和I 2对反应的有效进行都是必不可少的。研究并提出了一种以4-戊烯为底物的自由基型反应机理。
Iron-Catalyzed Reductive Dehydroxylation of Benzylic Alcohols Using Polymethylhydrosiloxane (PMHS)
作者:Sunggak Kim、Li Chan、Jazreel Lim
DOI:10.1055/s-0031-1289857
日期:2011.12
The combination of FeCl3 and PMHS is an efficient reducing system for the selective dehydroxylation of secondary benzylic alcohols, even in the presence of carbonyls, under very mild conditions.
We developed a chromium-catalyzed, photochemical, and linear-selective alkylation of aldehydes with alkylzirconium species generated in situ from a wide range of alkenes and Schwartz’s reagent. Photochemical homolysis of the C–Zr bond afforded alkyl radicals, which were then trapped by a chromium complex catalyst to generate the alkylchromium(III) species for polar addition to aldehydes. The reaction
Asymmetric Synthesis of Biaryl Diols via Dynamic Kinetic Resolution
作者:Jeonghun Cho、Kyungwoo Kim、Jaiwook Park、Mahn‐Joo Kim
DOI:10.1002/bkcs.12337
日期:2021.7
We have developed a protocol incuding dynamic kinetic resolution as the key step for the asymmetricsynthesis of biaryl diol stereoisomers. The two aryl alkanols as the starting materials were cross-coupled by palladium catalysis to give dl- and meso-diol, which were then subject to chemoenzymatic dynamic kinetic resolution (DKR) for the transformation into single stereoisomeric diol diester. Diol
我们开发了一个协议,包括动态动力学分辨率作为联芳二醇立体异构体不对称合成的关键步骤。两个芳基链烷醇作为起始材料是交叉耦合的由钯催化,得到DL -和内消旋-二醇,然后将其经受化学酶促动态动力学拆分( DKR)用于转化成单立体异构体的二醇二酯。二醇二酯最终脱酰化得到相应的联芳二醇立体异构体。化学酶促 DKR 使用基于钌的外消旋化催化剂和 ( R ) 选择性脂蛋白脂肪酶进行。总共 17 ( R , R )-二醇,包括 7 C 2合成了具有优异对映纯度 (>99% ee ) 的 -对称二醇。
A new method for alkylation of aromatic aldehydes using alkylboron chloride derivatives in the presence of oxygen
作者:George W Kabalka、Zhongzhi Wu、Yuhong Ju
DOI:10.1016/s0040-4020(02)00237-5
日期:2002.4
Reactions of aromatic aldehydes with alkylboron chloride derivatives in the presence of oxygen have been investigated. Dialkylboron chlorides react with aryl aldehydes to produce arylalkylmethanols in good to excellent yields. Under the same reaction conditions, alkylboron dichlorides lead to the formation of arylalkyl chlorides.