RuH 2 (PPh 3 ) 4 -catalyzed reaction of nitriles with terminal alkynes proceeds highly efficiently under neutral conditions to give the corresponding Michael adducts. Furthermore, 1,3-dicarbonyl compounds react with terminal alkynes at the α-position to afford the exo-methylene compounds with high regioselectivity under neutral conditions. The regioselectivity depends upon the change of substrates
RuH 2 (PPh 3 ) 4 催化的腈与末端炔烃的反应在中性条件下高效进行,得到相应的迈克尔加合物。此外,1,3-二羰基化合物在α-位与末端炔烃反应,在中性条件下提供具有高区域选择性的外亚甲基化合物。区域选择性取决于底物的变化。提出了精确的机制。
Asymmetric reduction of ethynyl ketones and ethynylketoesters by secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus †
作者:Christian Heiss、Robert S. Phillips
DOI:10.1039/b001329n
日期:——
Secondaryalcoholdehydrogenase (SADH) fromThermoanaerobacterethanolicus, an NADP-dependent, thermostable oxidoreductase, reduces ethynyl ketones and ethynylketoesters enantioselectively to the corresponding propargyl (propargyl = prop-2-ynyl) alcohols. Ethynyl ketones, in general, are reduced with moderate enantioselectivity (with the exception of 4-methylpent-1-yn-3-one, which gives the (S)-alcohol