Rh<sup>III</sup>-Catalyzed Regioselective Preparation of 3-Hetero-Substituted Isocoumarins from Aryl Carboxylic Acids and Alkynes
作者:Lijuan Song、Jing Xiao、Wanrong Dong、Zhihong Peng、Delie An
DOI:10.1002/ejoc.201601330
日期:2017.1.10
An oxygen-mediated annulation reaction has been reported herein. Various 3-hetero-substituted isocoumarins were successfully prepared with high efficiency (yields up to 88 %) and good functional-group tolerance (35 examples) in the presence of a rhodium catalyst. A plausible mechanism has also been proposed that shows the high regioselectivity mostly likely originates from the electron-density difference
A simple and mild methodology for the directsynthesis of alkynylphosphonates is presented. The reaction of a variety of terminalalkynes with dialkyl phosphites in the presence Cu2O (14 mol %) led to the formation of the corresponding alkynylphosphonates in good to excellent yields. Reactions are performed under air, in acetonitrile as solvent, and in the absence of base or ligand additives. This
Aerobic oxidative alkynylation of H-phosphonates and amides: an efficient route for the synthesis of alkynylphosphonates and ynamides using a recyclable Cu–MnO catalyst
作者:Harshvardhan Singh、Tapan Sahoo、Chiranjit Sen、Sunil M. Galani、Subhash Chandra Ghosh
DOI:10.1039/c9cy00275h
日期:——
and efficient route for the synthesis of alkynylphosphonates and ynamides by aerobic oxidative alkynylation of H-phosphonates and amides with both aliphatic and aromatic alkynes using our synthesized recyclable heterogeneous Cu–MnO catalyst has been developed. The phosphorylation was carried out under base- and ligand-free conditions, and in the presence of air as the sole oxidant. The reaction is compatible
Mukaiyama reagent-promoted metal-free preparation of alkynyl sulfones and phosphonates under mild conditions
作者:Danyang Qi、Wanrong Dong、Zhihong Peng、Yingjun Zhang、Delie An
DOI:10.1016/j.tet.2019.06.035
日期:2019.8
An efficient and mild route for the formation sulfur or phosphor-substituted alkynes was herein demonstrated. The Mukaiyama reagent-mediated transformation started from easily-accessible substrates without carbon-carbon triple bonds, and the reaction proceeded undermildconditions (room temperature) in a one-pot manner, requiring for no transition metal-catalysts. The practical protocol featured for
Base-Induced One-Pot Preparation of N- or P-Substituted Alkynes
作者:Yang Zhang、Yanqin Zhang、Jing Xiao、Zhihong Peng、Wanrong Dong、Delie An
DOI:10.1002/ejoc.201501092
日期:2015.12
An efficient method for the formation of C(sp)–N or C(sp)–P bonds is described. The facile transformation proceeds under mild conditions (0 or –20 °C) in a one-pot manner, and does not require transition-metal catalysts. The base-induced protocol exhibits good functional group tolerance (up to 44 examples) and high efficiency (up to 94 % yield) towards rare heteroatom-substituted acetylenes (N or P)