Thiourea participation in [3+2] cycloaddition with donor–acceptor cyclopropanes: a domino process to 2-amino-dihydrothiophenes
作者:Ming-Sheng Xie、Guo-Feng Zhao、Tao Qin、Yong-Bo Suo、Gui-Rong Qu、Hai-Ming Guo
DOI:10.1039/c8cc09595g
日期:——
The Yb(OTf)3-catalyzed [3+2] cycloaddition of donor–acceptor cyclopropanes with thiourea offers an efficient route to diverse 2-amino-4,5-dihydrothiophenes (up to 92% yield), in which optically active 2-amino-dihydrothiophenes can be produced from enantiomerically pure cyclopropanes. Thiourea, which is an odorless and cheap reagent, provides a CS double bond, serves as an amino source, and functions
Yb(OTf)3催化的供体-受体环丙烷与硫脲的[3 + 2]环加成反应提供了一种有效的途径来制备各种2-氨基-4,5-二氢噻吩(产率高达92%),其中旋光性2-氨基-二氢噻吩可由对映体纯的环丙烷产生。硫脲是一种无味且廉价的试剂,具有C S双键,可作为氨基源,并在该反应中用作脱碳烷氧基化试剂。初步的机理研究表明,该反应经历了依次的[3 + 2]环加成/脱氨基/脱羧过程。