86707-46-2Relevant articles and documents
ACID CATALIZED RING CLOSURE REACTINOS OF ELECTROPHILIC ALKENES
Verhe, Roland,Kimpe, Norbert De,Courtheyn, Dirk,Buyck, Laurent De,Schamp, Niceas
, p. 3649 - 3660 (2007/10/02)
Treatment of α-acyl-α,β-unsaturated ketones with sulfuric acid or dimethylformamide-hydrogen chloride or p-toluenesulfonic acid gave rise to 3-acyl-2-alkyl-4,5-dihydrofurans.Similar cyclization of α-acyl-α,β-unsaturated esters initially afforded 3-alkoxycarbonyl-2-alkyl-4,5-dihydrofurans which were transformed into 2-acylbutanolides on further reaction with sulfuric acid.This acid catalized cyclization is strongly dependent upon the substitution pattern of the electrophilic alkenes, the acid used and reaction conditions.