Photoexcited arylketones catalyze the direct chlorination of C(sp3)–H groups by N- chlorosuccinimide. Acetophenone is the most effective catalyst for functionalization of unactivated C–H groups while benzophenone provides better yields for benzylic C–H functionalization. Activation of both acetophenone and benzophenone can be achieved by irradiation with a household compact fluorescent lamp. This light-dependent
Organocatalytic Chlorination of Alcohols by P(III)/P(V) Redox Cycling
作者:Lars Longwitz、Stefan Jopp、Thomas Werner
DOI:10.1021/acs.joc.9b00741
日期:2019.6.21
system for the chlorination of alcohols under Appel conditions was developed. Benzotrichloride is used as a cheap and readily available chlorinating agent in combination with trioctylphosphane as the catalyst and phenylsilane as the terminal reductant. The reaction has several advantages over other variants of the Appel reaction, e.g., no additional solvent is required and the phosphane reagent is used
The selectiveconversion of one inactive C(sp3)-Cl bond of 1,2-dichloroethane (DCE) into C(sp3)-C(sp2) linkages for access to β-chloroethylarenes is presented here. The key to achieve the required reactivity and chemoselectivity in this synthetic method was the utilization of nickel and combinatorial nitrogen ligands as catalytic system. Synthetic advantages of this coupling chemistry included the