In the presence of phosphine catalyst and pinacolborane, ynones undergo 1,2-reduction while ynoates undergotrans-hydroboration. Mechanistic insights into the two competing pathways lay grounds for control of selectivity in these processes.
syntheses of the allenes (±)-1, (±)-4 and (±)-6 as well as of the enriched samples (-)-1, (-)-4 and (-)-6 are described. 1H NMR shifts and splittings induced by a mixture of the achiral salt Ag(fod) and the opticallyactive complex (+)-Yb(hfbc)3 are given. This procedure is recommended by the magnitude of such splittings as a means of determining the enantiomeric purity of 1,3-disubstituted allenic hydrocarbons
描述了烯丙基(±)-1,(±)-4和(±)-6以及富集样品(-)-1,(-)-4和(-)-6的合成。给出了由非手性盐Ag(fod)和旋光络合物(+)-Yb(hfbc)3的混合物引起的1 H NMR位移和分裂。这种分离的程度推荐该方法作为确定1,3-二取代的烯丙基烃的对映体纯度的手段。(-)-1和(-)-5的结果代表了该绝对方法的首次应用。
Reaction of propargylic substrates with organocopper species. Synthetic aspects
作者:Timothy L. Macdonald、David R. Reagan、Raymond S. Brinkmeyer
DOI:10.1021/jo01311a037
日期:1980.11
MACDONALD T. L.; REAGAN D. R.; BRINKMEYER R. S., J. ORG. CHEM., 1980, 45, NO 23, 4740-4747
作者:MACDONALD T. L.、 REAGAN D. R.、 BRINKMEYER R. S.