Treatment of 2-benzhydrylidenetetrahydrofuran with perbenzoic or perphthalic acid does not yield the expected spiroepoxy ketal. Action of t-butyl hypochlorite or N-bromosuccininimide on the benzhydrylidenetetrahydrofuran does not give the corresponding halohydrin, but leads to 2, 2-diphenyl-3-ketotetrahpdropyran by a rearrangement involving ring enlargement. Treatment of ethyl a-propionylpropionate with ethylene chlorohydrin and ...
