Alkynyl<i>N</i>-Nosylhydrazones: Easy Decomposition to Alknynl Diazomethanes and Application in Allene Synthesis
作者:Yang Yang、Zhaohong Liu、Alessio Porta、Giuseppe Zanoni、Xihe Bi
DOI:10.1002/chem.201701462
日期:2017.7.6
reaction with boronic acids under metal-free conditions is reported, giving rise to a wide array of di- and trisubstituted allenes. Preliminary mechanistic investigations demonstrated that γ-protodeboration of propargyl boric acid was responsible for the initial allene formation. This methodology based on the nosyl group allows for novel transformations that involve an alkynylcarbene transient species
Silver(<scp>i</scp>)-mediated highly enantioselective synthesis of axially chiral allenes under thermal and microwave-assisted conditions
作者:Vanessa Kar-Yan Lo、Cong-Ying Zhou、Man-Kin Wong、Chi-Ming Che
DOI:10.1039/b914516h
日期:——
Silver(I) salts mediated stereospecifictransformation of opticallyactive propargylamines to axially chiral allenes with excellent enantioselectivities (17 examples with 96-99% ee; one substrate with 91% ee) without subsequent racemization.