A practical method for the asymmetric transferhydrogenation of α‐substituted ketones was developed utilizing oxo‐tethered N‐sulfonyldiamine‐ruthenium complexes. Reduction by HCO2H and HCO2K in a mixed solvent of EtOAc/H2O allowed for the selective synthesis of halohydrins from 2‐bromoacetophenone (98%) and 2‐chloroacetophenone (>99%), leading to suppressed undesired side reactions stemming from formylation
Electrochemically driven stereoselective approach to <i>syn</i>-1,2-diol derivatives from vinylarenes and DMF
作者:Da Sol Chung、Steve H Park、Sang-gi Lee、Hyunwoo Kim
DOI:10.1039/d1sc00760b
日期:——
vinylarenes with N,N-dimethylformamide (DMF). The newly developed system obviates the need for transition metal catalysts or external oxidizing agents, thus providing an operationally simple and efficient route to an array of protected syn-1,2-diols in a single step. This reaction proceeds via an electrooxidation of olefin, followed by a nucleophilicattack of DMF. Subsequent oxidation and nucleophilic capture
Metal‐Free Electrocatalytic Diacetoxylation of Alkenes
作者:Jef R. Vanhoof、Pieter J. De Smedt、Jan Derhaeg、Rob Ameloot、Dirk E. De Vos
DOI:10.1002/anie.202311539
日期:2023.12.4
A highly efficient electrocatalytic 1,2-dioxygenation of alkenes utilizing readily available materials in ambient conditions is developed. The protocol is widely applicable to aliphatic and aromatic alkenes with excellent faradaic efficiencies and yields of up to 96 %. The versatility of the method is expanded with alkenoic acids towards lactone derivatives and with other carboxylic acids like HCOOH
Behal, Annales de Chimie (Cachan, France), 1900, vol. <7> 20, p. 421
作者:Behal
DOI:——
日期:——
Chemoselective Deoxygenation of 2° Benzylic Alcohols through a Sequence of Formylation and B(C
<sub>6</sub>
F
<sub>5</sub>
)
<sub>3</sub>
‐Catalyzed Reduction
作者:Sven C. Richter、Martin Oestreich
DOI:10.1002/ejoc.202100148
日期:2021.4.15
A sequence of formylation and B(C6F5)3‐catalyzed reduction of the resulting formate with Et3SiH enables the chemoselective deoxygenation of secondary (2°) benzylic in the presence of primary (1°) benzylic and tertiary (3°) non‐benzylic alcohols. Both steps are chemoselective with the formylation favoring 1° and 2° over 3° and the reduction favoring 2° over 1° (Ar=aryl, Alk=alkyl).
一系列的甲酰化反应和B(C 6 F 5)3催化的Et 3 SiH还原生成的甲酸使得在存在伯(1°)苄基和叔(3°)的情况下仲(2°)苄基的化学选择性脱氧成为可能)非苄醇。这两个步骤都是化学选择性的,其中甲酰化相对于3°有利于1°和2°,而还原相对于1°有利于2°(Ar =芳基,Alk =烷基)。