VINYLIC ORGANOBORANES .12. SYNTHESIS OF (Z)-1-HALO-1-ALKENES VIA HYDROBORATION OF 1-HALO-1-ALKYNES FOLLOWED BY PROTONOLYSIS
VINYLIC ORGANOBORANES .12. SYNTHESIS OF (Z)-1-HALO-1-ALKENES VIA HYDROBORATION OF 1-HALO-1-ALKYNES FOLLOWED BY PROTONOLYSIS
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DOI：
10.1021/jo00287a017
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发表时间：
1989-12-22
影响因子：
3.6
通讯作者：
BHAT, NG
中科院分区：
文献类型：
--
作者：
BROWN, HC;BLUE, CD;BHAT, NG
提出了以1-卤代-1-烯烃为原料合成(Z)-1-卤代-1-烯烃的实用条件。1-卤代-1-炔烃与二环己基硼烷(CHx2BH)或9-硼二环[3.3.1]正十一烷(9-BBN)反应，只生成相应的B-((Z)-1-卤代-1-烯基)二烷基硼烷1，未发现二氢硼化产物。报道了用乙酸乙酯对1进行质子化反应，生成(Z)-1-卤代-1-烯烃的一般步骤。使用CHX2BH在戊烷中合成这些卤代烯特别方便。在该溶剂中，CHx2BH的合成、随后的硼氢化和质子化以及乙醇胺脱除硼烷残留物的反应都进行得很顺利和迅速，产率接近定量。
Practical conditions have been developed for synthesizing (Z)-1-halo-1-alkenes from 1-halo-1-alkynes. The reaction of 1-halo-1-alkynes with dicyclohexylborane (Chx2BH) or with 9-borabicyclo[3.3.1]nonane (9-BBN) gives exclusively the corresponding B-((Z)-1-halo-1-alkenyl)dialkylboranes 1. No dihydroboration products were found. A general procedure is reported for protonolyzing 1 with AcOH, yielding the (Z)-1-halo-1-alkenes. The synthesis of these haloalkenes is particularly convenient using Chx2BH in pentane. In this solvent, the synthesis of Chx2BH, the subsequent hydroboration and protonolysis, and the removal of the borane residue with ethanolamine all go smoothly and rapidly with nearly quantitative yields.