Reactions of 2,2-dimethyl-1,1-diphenylpropan-1-ol with acidic reagents: a reinvestigation of the dehydration products and isolation of a sulphonation product

Abstract

Dehydration of 2,2-dimethyl-1,1 -diphenylpropan-1-ol (1) with acidic reagents has been reinvestigated and shown to give 2-methyl-3,3-diphenylbut-1-ene (2), which rearranges rapidly under acidic conditions to give 3-methyl-2,3-diphenylbut-1-ene (3). Some earlier claims to have prepared the olefin (2) are shown to be erroneous. Prolonged treatment of the alcohol (1) with concentrated sulphuric acid gives a compound which appears to be a sultone.