Regio-and stereoselectivity of diethylaluminum azide opening of trisubstituted epoxides and conversion of the 3 azidohydrin adducts to isoprenoid aziridines

…, JL Bailey, JW Lockner, RM Coates

Index: Davis, Chad E.; Bailey, Jessica L.; Lockner, Jonathan W.; Coates, Robert M. Journal of Organic Chemistry, 2003 , vol. 68, # 1 p. 75 - 82

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Citation Number: 38

Abstract

The regioisomer ratios (3°, 2°/2°, 3°), and in some cases the stereochemistry, of vicinal azidohydrins formed in reactions of 11 trisubstituted terpene epoxides with Et2AlN3 in toluene are reported. The more highly substituted azide usually predominated (3°, 2°/2°, 3° ratios≥ 40: 1 to 2.5-1) in accord with a Markovnikov orientation and an SN1-like transition state. Reversed regioisomer ratios were observed with 6, 7-epoxygeranyl acetate (1: 2.5) ...