Sulfonated charcoal, a mild and efficient reagent for the preparation of cyclic acetals, dithioacetals and benzodioxepines
作者:Haris K. Patney
DOI:10.1016/s0040-4039(00)92642-x
日期:1991.1
1,3-Dioxolanes, 1,3-Ditholanes and 1,5-dihydro-3-2,4-benzodioxepines were prepared by the direct condensation of carbonyl compounds with 1,2-ethanediol, 1,2-ethanedithiol or 1,2-benzenedimethanol under the heterogeneous conditions of sulfonated charcoal catalyst.
synthetic way leading to 1,4-benzodithians (2) variously substituted at the benzenoid ring. The ready availability of these latter makes the 1,4-benzodithian system itself being regarded as appealing intermediate to obtain, after sulfur replacement or removal, aromatic compounds that cannot be prepared under the usual electrophilicsubstitution conditions.
A new route to 2,3-dihydro-1,4-benzoxathiine and 2,3-dihydro-1,4-benzodithiine
作者:James Y. Satoh、Amos M. Haruta、Christopher T. Yokoyama、Yasuo Yamada、Masakatsu Hirose
DOI:10.1039/c39850001645
日期:——
The ethylene monothioacetals and dithioacetals of alkylcyclohexanones react with copper(II) bromide to give 2,3-dihydro-1,4-benzoxathiine and 2,3-dihydro-1,4-benzodithiine derivatives, respectively.