The synthesis of ynamides in water was achieved by a micellarcatalysis strategy using rosin‐based surfactant APGS‐550‐M, which can be easily prepared from natural abundant biomass.
transformation of alkynes by controlled manipulation of TsNBr2 mediated process. Alkynes could be readily converted to ketones and α-bromoketones via an oxybromination–debromination sequence. When alkynes are treated successively with TsNBr2, KI and Na2SO3 in a mixture of acetone and water at roomtemperature, corresponding ketones were obtained. On the other hand, treatment of alkynes with TsNBr2 and
通过控制TsNBr 2介导的过程,开发了炔烃的氧化转化的新方法。炔烃可以很容易地通过氧溴化-脱溴序列转化为酮和α-溴代酮。在室温下,在丙酮和水的混合物中依次用TsNBr 2,KI和Na 2 SO 3处理炔烃时,可获得相应的酮。另一方面,用TsNBr 2和Na 2 SO 3处理炔烃在室温下,在乙酸乙酯,丙酮和水的混合物中,可生成相应的α-溴代酮。还可以在室温下使用TsNBr 2在很短的时间内由相应的炔烃合成1-溴炔烃。在所有情况下,都可获得相应产品的优异收率。
Rapid access to unsymmetrical 1,3-diynes and 2,5-disubstituted thiophenes under ligand and Pd/Ni-free Cu-catalysis
作者:Maddali L. N. Rao、Sk Shamim Islam、Priyabrata Dasgupta
DOI:10.1039/c5ra15705f
日期:——
A Pd/Ni-free copper-catalysed tandem synthesis was realized for rapid access to unsymmetrical 1,3-diynes from 1,1-dibromoalkenes and terminal alkynes. This method was extended to the straightforward synthesis of unsymmetrical 2,5-disubstitutedthiophenes in a one-pot operation.
Highly efficient and recyclable catalyst for the direct chlorination, bromination and iodination of terminal alkynes
作者:Wei Shi、Zhipeng Guan、Peng Cai、Hao Chen
DOI:10.1016/j.jcat.2017.07.019
日期:2017.9
Direct halogenation, including chlorination, bromination and iodination of terminalalkynes, are of great importance in organic synthesis. Here an efficient and recyclable nano-Ag/g-C3N4 catalyst system was developed and proved to be remarkably active with 39 examples varied from chlorination, bromination to iodination, of which 14 runs have yielded more than 95% of the product. Recycling of the catalyst
直接卤化,包括末端炔烃的氯化,溴化和碘化,在有机合成中非常重要。在此,开发了一种有效且可循环利用的纳米Ag / gC 3 N 4催化剂体系,并证明其具有显着的活性,从氯化,溴化到碘化的39种实例中,有14种的收率超过了95%。在几次运行后,也实现了催化剂的再循环而没有明显的活性损失:即使在苯乙炔的溴化过程中进行了5次运行,也观察到99%的收率。该催化剂系统成本低廉且易于制备,使得该方法通用,方便且经济。