Diastereoselective conjugate addition to 3-(p-tolylsulphinyl)chromone: a route to chiral 2-substituted chroman-4-ones
作者:Suthiweth T. Saengchantara、Timothy W. Wallace
DOI:10.1039/c39860001592
日期:——
Conjugate addition of lithium dimethylcuprate to 3-(p-tolylsulphinyl)chromone (1) proceeds with at least 90% diastereoselectivity, and the products from (S)-(1) can be converted into chiral 2-methylchroman-4-one (–)-(16).
SAENGCHANTARA SUTHIWETH T.; WALLACE T. W., J. CHEM. SOC. CHEM. COMMUN.,(1986) N 21, 1592-1595
作者:SAENGCHANTARA SUTHIWETH T.、 WALLACE T. W.
DOI:——
日期:——
Conjugate addition to 3-(ptolylsulphinyl)chromone: a route to 2-substituted chromones and chiral substituted chroman-4-ones
作者:Suthiweth T. Saengchantara、Timothy W. Wallace
DOI:10.1016/s0040-4020(01)96020-x
日期:1990.1
3-(p-Tolylsulphinyl)chromone 3a undergoes diastereoselectiveconjugateaddition of lithium dimethylcuprate, producing a mixture of 2-methyl-3-(p-tolylsulphinyl)chroman-4-ones. Heating the mixture to 140°C gives 2-methylchromone in quantitative yield. Desulphurisation of the mixed products from (S)-3a gives (S)-2-methylchroman-4-one with 90% e.e. Chelation of the carbonyl and sulphoxide oxygens during