Potassium Fluoride on Alumina: Synthesis of O-Aryl N,N-Dimethylthiocarbamates and their Rearrangement into S-Aryl N,N-Dimethyl-Thiocarbamates Under Microwave Irradiation
摘要:
A series of O-aryl N,N-dimethyl thiocarbamates have been prepared by the reaction of dimethylthiocarbamoyl chloride with phenols absorbed on potassium fluoride on alumina. The rearrangement of O-aryl N,N-dimethylthiocarbamate into S-aryl N,N-dimethyl thiocarbamate under microwave irradiation was also studied. The use of conductive support like graphite or silicon carbide allow these rearrangements although the O-aryl N,N-dimethylthiocarbamates have very low dielectric lost.
作者:Thibault Gendron、Raul Pereira、Hafsa Y. Abdi、Timothy H. Witney、Erik Årstad
DOI:10.1021/acs.orglett.9b04280
日期:2020.1.3
Herein, we report that iron(II)/ammonium persulfate in aqueous acetonitrile mediates the Newman-Kwart rearrangement of O-aryl carbamothioates. Electron-rich substrates react rapidly under moderate heating to afford the rearranged products in excellent yields. The mild conditions, rapid reaction rates, and suitability for scale up offers immediate practical benefits to access functionalized thiophenols
The Newman-Kwart Rearrangement of<i>O</i>-Aryl Thiocarbamates: Substantial Reduction in Reaction Temperatures through Palladium Catalysis
作者:Jeremy N. Harvey、Jesús Jover、Guy C. Lloyd-Jones、Jonathan D. Moseley、Paul Murray、Joseph S. Renny
DOI:10.1002/anie.200903908
日期:2009.9.28
Newman–Kwart rearrangement allows an escape from the harsh thermal conditions of the standard uncatalyzed reaction (see scheme). Mechanistic investigations, employing kinetic, isotopic labelling (2H, 18O, 34S) and DFT studies, suggest that the reaction proceeds through a five‐centred Pd–S coordinated oxidative addition, with intermolecular exchange of aryl and thiocarbamate moieties through dimerization of the
The thiocarbamoylation of internal alkynes to produce tetrasubstituted β-aminocarbonyl vinyl sulfides was demonstrated using a nickel catalyst. This reaction was successful with a wide variety of substituents, and gave the syn-adducts exclusively.
Cu(OAc)2-Catalyzed Thiolation of Acyl C-H Bonds with Thiols Using TBHP as an Oxidant
作者:Yan-qin Yuan、Jian-nan Xiang、Sheng-rong Guo
DOI:10.1055/s-0032-1318188
日期:——
Cu(OAc)(2)-promoted TBHP oxidative coupling reaction of formamides with thiols successfully proceeded through direct C-H bond activation of formamides. The corresponding S-phenyl dialkyl thiocarbamate compounds were formed with high yield under solvent-free conditions.
AlCl3-promoted thiolation of acyl C–H bonds with arylsulfonyl hydrazides
AlCl3-promoted thiolation of acyl C-H bonds with arylsulfonyl hydrazides was developed, which represents an effective synthesis of S-aryl thiocarbamates via C-S bond formation reaction. (C) 2015 Elsevier Ltd. All rights reserved.