作者:Louis C. Morrill、Samuel M. Smith、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/jo402591v
日期:2014.2.21
Isothiourea HBTM-2.1 promotes the catalytic asymmetric alpha-functionalization of 3-alkenoic acids through formal [2 + 2] cycloadditions with N-tosyl aldimines and formal [4 + 2] cycloadditions with either 4-aryltrifluoromethyl enones or N-aryl-N-aroyl diazenes, providing useful synthetic building blocks in good yield and with excellent enantiocontrol (up to >99% ee). Stereodefined products are amenable to further synthetic elaboration through manipulation of the olefinic functionality.