Institute for Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany.
Chemistry. 2012 Apr 10;18(15):4687-91. doi: 10.1002/chem.201103691. Epub 2012 Feb 29.
A calcium-catalyzed direct reduction of propargylic alcohols and ethers has been accomplished by using triethylsilane as a nucleophilic hydride source. At room temperature a variety of secondary propargylic alcohols was deoxygenated to the corresponding hydrocarbons in excellent yields. Furthermore, for the first time, a catalytic deoxygenation of tertiary propargylic alcohols was generally applicable. The same protocol was suitable for an efficient reduction of secondary as well as tertiary propargylic methyl, benzyl and allyl ethers. Substrates containing an additional keto-, ester or secondary hydroxyl function were reduced with exceptional chemoselectivity at the propargylic position.
三乙硅烷作为亲核氢源，实现了钙催化的炔丙醇和醚的直接还原。在室温下，各种仲炔丙醇以优异的收率脱氧生成相应的烃。此外，这是首次普遍适用于叔炔丙醇的催化脱氧。相同的方案适用于仲和叔炔丙基甲基、苄基和烯丙基醚的有效还原。含有额外的酮、酯或仲羟基官能团的底物在炔丙位具有极好的化学选择性还原。
