Parham Cyclization

W. E. Parham et al., J. Org. Chem. 40, 2394 (1975).

Four- to seven-membered ring annulation of aryl bromides bearing ortho side chains having an electrophilic moiety, accomplished by halogen-metal exchange and subsequent nucleophilic ring closure:



Synthetic application: M. R. Paleo et al., J. Org. Chem. 40, 2029 (1975); A. Couture et al., Chem. Commun. 1994; 1329; M. I. Collado et al., Tetrahedron Letters 37, 6193 (1996); S. D. Larsen, Synlett 1997; 1013; A. Ardeo et al., Tetrahedron Letters 41, 5211 (2000). Review: W. E. Parham, C. K. Bradsher, Accts. Chem. Res. 15, 300-305 (1982).