Sulfoxonium ylides as carbene precursors couple smoothly with thioureas in the presence of 5 mol% of rhodium(II) acetate dimmer via carbenoid insertion to afford the corresponding 2-aminothiazoles with high chemoselectivity, providing a facile and efficient approach to access a variety of 2-aminothiazole derivatives with good functional groups tolerance.
copper-catalyzed coupling of oximeacetates with isothiocyanates. Various 4-substituted and 4,5-disubstituted 2-aminothiazoles were formed smoothly under mild reaction conditions. This process involved copper-catalyzed N–O bond cleavage, activation of vinyl sp2 C–H bonds, and C–S/C–N bond formations. It is noteworthy that the oximeacetates were used not only as a substrate but also as a single oxidant
Several straightforward and practical processes have been established for the construction of 2-aminothiazoles, 1,3-thiazoles and 1,3-selenazoles from aryliodoazides. These strategies successfully proceed with a wide spectrum of substituted thioamides and its derivatives producing the resulting five-membered heterocycles obtained in satisfactory yields. The unique features of these protocols are operational
Highly Efficient Heterogeneous Copper-Catalysed Coupling of Oxime Acetates with Isothiocyanates Leading to 2-Aminothiazoles
作者:Yuxin Tuo、Fang Yao、Yang Liao、Mingzhong Cai
DOI:10.3184/174751917x14894997017739
日期:2017.4
The heterogeneous coupling reaction of oxime acetates with isothiocyanates was achieved at 110 °C in toluene in air in the presence of a bidentate nitrogen-functionalised MCM-41-immobilised copper(I) complex (MCM-41-2N-CuI) with Cs2CO3 as base to afford a variety of 2-aminothiazoles in good yields. The MCM-41-2N-CuI catalyst can be easily recovered by a simplefiltration and reused at least eight times