Electrophotocatalytic diamination of vicinal C–H bonds
作者:Tao Shen、Tristan H. Lambert
DOI:10.1126/science.abf2798
日期:2021.2.5
carbon-hydrogen (C–H) bonds to carbon–nitrogen (C–N) bonds is a highly valued transformation. Existing strategies typically accomplish such reactions at only a single C–H site because the first derivatization diminishes the reactivity of surrounding C–H bonds. Here, we show that alkylated arenes can undergo vicinal C–H diamination reactions to form 1,2-diamine derivatives through an electrophotocatalytic strategy
Substituted Hantzsch esters can act as radical reservoirs in photoredox reactions, steadily releasing a carbon radical and a hydrogen atom radical in the absence of an additional electron acceptor. We propose that radical release by substituted Hantzsch esters occurs via a mechanism involving an internal redox cycle. Cinnamidecinnamides, styrenes, α,β‐unsaturated acids, and diarylethenes could be alkylated
combination of “TiCl2(cat)” and Zn (cat=catecholate) facilitates the homolytic cleavage of “non-activated” alcohol C−O bonds. All aliphatic primary, secondary and tertiary alcohols serve as good substrates. This method was applied to radical conjugate addition reactions successfully, and mechanistic studies indicate that alkyl chlorides are not intermediates. The active species is a 1 : 2 complex of alkoxide
作者:Cornelia S. Buettner、Michael Schnürch、Katharina Bica-Schröder
DOI:10.1021/acs.joc.2c01304
日期:2022.8.19
aryl-alkenes affording C–C bonds using aryl-alkenes and alkyliodides. We demonstrate the formation of various hydroalkylation products in excellent yields, with primary, secondary, and tertiary alkyliodides being tolerated in the reaction. Mechanistic experiments reveal a pathway consisting of halogen atom transfer followed by a radical-polar crossover mechanism delivering the desired hydroalkylation products
Direct conversion of carboxylic acids to free thiols <i>via</i> radical relay acridine photocatalysis enabled by N–O bond cleavage
作者:Dmitry L. Lipilin、Mikhail O. Zubkov、Mikhail D. Kosobokov、Alexander D. Dilman
DOI:10.1039/d3sc05513b
日期:——
basic chemical compounds with diverse utility and widespread reactivity. However, the direct conversion of unprotected acids to thiols is hampered due to a fundamental problem – free thiols are incompatible with the alkyl radicals formed on decarboxylation of carboxylic acids. Herein, we describe a concept for the direct photocatalytic thiolation of unprotected acids allowing unprotected thiols and their