β-Carbonyloxy sulfides fragment when heated with silica or alumina to produce reactive episulfonium ion intermediates. Intramolecular activation of the leaving group and concurrent protection of a nitrogen or oxygen nucleophile via a cyclic carbamate or carbonate leads to the formation of pyrrolidines or cyclic ethers.
β-羰氧基
硫化物在与
二氧化硅或氧化铝一起加热时会发生碎片,生成反应性环鎓离子中间体。离去基团的分子内活化和氮或氧亲核试剂通过环状
氨基甲酸酯或
碳酸酯的同时保护导致
吡咯烷或环状醚的形成。