Concomitant Epoxide Deoxygenation and Deacetylation of Glycidyl Acetates Induced by Telluride Ion
摘要:
Treatment of glycidyl acetates with telluride ion (Te2-) produced by reduction of elemental Te with LiEt(3)BH yields allylic alcohols by loss of the epoxide oxygen atom and the acetyl group from the ester. If the glycidyl acetate is disubstituted at C-3, a rearrangement to an isomeric allylic alcohol competes with the deoxygenation-deacetylation. Triethylborane, a byproduct in the reduction of Te, is believed to play an important role as a Lewis acid since when it is absent or removed by addition of fluoride ion the reaction is extremely slow.
Concomitant Epoxide Deoxygenation and Deacetylation of Glycidyl Acetates Induced by Telluride Ion
作者:Donald C. Dittmer、Yanzhi Zhang、Robert P. Discordia
DOI:10.1021/jo00084a016
日期:1994.3
Treatment of glycidyl acetates with telluride ion (Te2-) produced by reduction of elemental Te with LiEt(3)BH yields allylic alcohols by loss of the epoxide oxygen atom and the acetyl group from the ester. If the glycidyl acetate is disubstituted at C-3, a rearrangement to an isomeric allylic alcohol competes with the deoxygenation-deacetylation. Triethylborane, a byproduct in the reduction of Te, is believed to play an important role as a Lewis acid since when it is absent or removed by addition of fluoride ion the reaction is extremely slow.
Palladium-Catalyzed γ-Selective and Stereospecific Allyl−Aryl Coupling between Allylic Acetates and Arylboronic Acids
Allyl-aryl coupling between allylic acetates and arylboronicacids took place in the presence of catalytic amounts of Pd(OAc)(2), 1,10-phenanthroline, and AgSbF(6) with high gamma-selectivity and E/Z-selectivity. The reaction of an optically active allylic acetates with an alpha-stereogenic center proceeded with excellent alpha-to-gamma chirality transfer with syn-selectivity and gave the corresponding