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
An Electrocatalytic Newman–Kwart-type Rearrangement
作者:Timo Broese、Arend F. Roesel、Adrian Prudlik、Robert Francke
DOI:10.1021/acs.orglett.8b03257
日期:2018.12.7
An electrochemical approach toward rearrangement of O-aryl thiocarbamates to the corresponding S-aryl thiocarbamates is presented. The protocol requires only catalytic amounts of electric charge and allows for operation at room temperature. The electrolysis can be carried out with the simplest equipment, i.e., under galvanostatic conditions in an undivided cell. Furthermore, it is demonstrated that
Studies of the Thiocarbonyl Compounds. III. The Mechanism of the Thermal Rearrangement of Aryl Thionocarboxylates
作者:Aritsune Kaji、Yoshiaki Araki、Koshin Miyazaki
DOI:10.1246/bcsj.44.1393
日期:1971.5
The thermal rearrangement of aryl thionocarboxylates was kinetically investigated in diphenyl ether. The rate constants of the rearrangement of aryl N,N-dimethylthionocarbamates were well correlated with the σ− values, but the plots of the electron-releasing para-substituents deviated slightly on the lower side of the meta correlation line. A good linear free-energy relationship existed between the
Ambient-Temperature Newman–Kwart Rearrangement Mediated by Organic Photoredox Catalysis
作者:Andrew J. Perkowski、Cole L. Cruz、David A. Nicewicz
DOI:10.1021/jacs.5b11800
日期:2015.12.23
The Newman-Kwartrearrangement is perhaps the quintessential method for the synthesis of thiophenols from the corresponding phenol. However, the high thermal conditions required for the rearrangement of the requisite O-aryl carbamothioates often leads to decomposition. Herein, we present a general strategy for catalysis of O-aryl carbamothioates to S-aryl carbamothioates using catalytic quantities
Efficient C−S Bond Formation by Direct Functionalization of C(
<i>sp</i>
<sup>3</sup>
)−H Bond Adjacent to Heteroatoms under Metal‐Free Conditions
作者:Feng Zhao、Qi Tan、Dahan Wang、Jinjin Chen、Guo‐Jun Deng
DOI:10.1002/adsc.201900666
日期:2019.9.3
A simple and efficient method for the formation of C−Sbond via directfunctionalization of C(sp3)−H bond adjacent to heteroatoms was described under metal‐free conditions. In this work, stable and easily accessible sodium sulfinates were used as the thiolating agents to afford various aryl thioethers in moderate to excellent yields. Mechanistic explorations show that a radical pathyway is possibly