Electrophile-induced rearrangement of 1,2,4-trioxanes. Formation of 1-benzofuran and 2H-1-benzopyrans
作者:Charles W. Jefford、Jean-Claude Rossier、John Boukouvalas
DOI:10.1039/c39870000713
日期:——
10b-Tetramethyl-4a, 10b-dihydronaphtho[2,1-e][1,2,4]trioxane and its 3,3-spirocyclic cyclopentane analogue on treatment with an excess of trimethylsilyl trifuloromethanesulphonate for 10 min at 24 °C rearrange to give 2-(2-oxopropyl)-3-methyl-1-benzofuran in high yield; in similar fashion the 3-methyl, n-butyl, and phenyl derivatives of 3,10b-epidioxy-2,3,4a,10b-tetrahydro-6-methyl-1H-naphtho[2,1-b]pyran
3,3,6,10b-四甲基-4a,10b-二氢萘并[ 2,1- e ] [1,2,4]三恶烷及其3,3-螺环环戊烷类似物用过量的三甲基甲硅烷基三氟甲磺酸酯处理10分钟在24°C下重排,以高收率得到2-(2-氧丙基)-3-甲基-1-苯并呋喃;以类似的方式在3-甲基,正丁基,和苯基3,10b-epidioxy-2,3,4a的衍生物,10b-四氢-6-甲基-1- ħ -萘并[2,1- b ]吡喃,得到2-甲酰基-3-甲基(2 H)-1-苯并吡喃的3-氧代丁基,3-氧代庚基和3-苯基-3-氧代丙基衍生物。