Aluminum Chloride Catalyzed Reaction of Acetanilide with Pivalyl Chloride

Article abstract of DOI:10.1021/jo00178a016

Product development was studied in the aluminum chloride catalyzed reaction of acetanilide with pivalyl chloride. 3-tert-Butylacetanilide is the major product because of its relative resistance to dealkylation by reaction-produced HCl.At long reaction times all alkylation products are converted back to acetanilide with the only survivor being 2,2-dimethyl-5-tert-butyl-7-acetamidoindanone.The crystal structure of this compound was determined.It crystallized in the space group P_nma with cell constants a = 12.571 (3) Angstroem, b = 7.302 (1) Angstroem, c = 16.910 (3) Angstroem, V = 1552.24 Angstroem³, z = 4.Refinement of the 1224 data with F² <*> 3?(F²) resulted in discrepancy indices R₁ = 0.056 and R₂ = 0.074.A novel mechanism for formation of this indanone is proposed, involving nucleophilic attack by alkene on a protonated arene ring.