Efficient 1,8- and 1,9-asymmetric inductions in the Grignard reaction of δ- and ɛ-keto esters of 1,1′-binaphthalen-2-ols with an oligoether tether as the 2′-substituent: application to the synthesis of (−)-malyngolide
Arene-catalysed reductive lithiation of tetrahydrofuran: improved synthesis of 1,5-diols
作者:Diego J. Ramón、Miguel Yus
DOI:10.1016/s0040-4020(01)88496-9
日期:1992.1
The reductivecleavage of tetrahydrofuran at −78°C can be easily achieved by using an excess of lithium powder in the presence of BF3·OEt2 and a catalytic amount (<8%) of an arene (naphthalene, biphenyl, 4,4′- di-tert-butylbiphenyl or anthracene), the best results being obtained with naphthalene. The dianion prepared by this method reacts with carbonyl compounds yielding 1,5-diols.