trisubstituted thioureas of arylamines is presented, for the first time, using in situ generated dithiocarbamates of secondary amines. This strategy provides an excellent opportunity to access thioureas containing primary aryl amines. A non-isothiocyanate route to obtain thioureas is the advantage of this strategy, which may provide a useful route to synthesize a variety of biologically active derivatives of thioureas
Heterocycle Formation via Palladium-Catalyzed Intramolecular Oxidative C−H Bond Functionalization: An Efficient Strategy for the Synthesis of 2-Aminobenzothiazoles
作者:Laurie L. Joyce、Robert A. Batey
DOI:10.1021/ol900958z
日期:2009.7.2
N-Arylthioureas are converted to 2-aminobenzothiazoles via intramolecular C−S bond formation/C−H functionalization utilizing an unusual cocatalytic Pd(PPh3)4/MnO2 system under an oxygen atmosphere at 80 °C. This method eliminates the need for an ortho-halo substituted precursor, instead achieving direct functionalization of the ortho-aryl C−H bond. Mechanistic observations, including a large intramolecular