ACCELERATED REDUCTION OF ORGANIC SUBSTANCES WITH BORANES
申请人:Burkhardt Elizabeth
公开号:US20090082568A1
公开(公告)日:2009-03-26
In a process for the accelerated reduction of organic substrates, selected from the group consisting of ester, amides, nitriles, acids, ketones, imines or mixtures thereof, the substrates are reacted with an amine borane, sulfide borane or ether borane complex as a borane source in the presence of organic accelerator compounds containing both Lewis acidic and Lewis basic sites in their structure, of which the Lewis acidic site can coordinate with the carbonyl or nitrile or imine group of the substrate and the Lewis basic site can coordinate with the borane.
Direct observation of .alpha.-oxo ketenes formed from 1,3-dioxin-4-ones and the enols of .beta.-keto esters
作者:Beat Freiermuth、Curt Wentrup
DOI:10.1021/jo00007a008
日期:1991.3
The enol forms of beta-keto esters thermolyze to alcohols and alpha-oxo ketenes, which are characterized by low-temperature IR spectroscopy and on warming regenerate the beta-hydroxy-alpha,beta-unsaturated esters. The matrix isolated s-Z and s-E forms of alpha-oxo ketenes are characterized and photochemically converted into other conformers or sites. Matrix photolysis of 2,2,6-trimethyl-1,3-dioxin-4-one gives the s-Z acetylketene initially. Alpha-Oxo ketenes polymerize in the cold and dimerize only at elevated temperatures.