Alkyl 4-Chlorobenzoyloxycarbamates as Highly Effective Nitrogen Source Reagents for the Base-Free, Intermolecular Aminohydroxylation Reaction

Ethyl- (7), benzyl- (8), tert-butyl- (9), and fluorenylmethyl-4-chlorobenzoyloxycarbamates (10) have been prepared as storable and easy-to-prepare nitrogen sources for use in the intermolecular Sharpless aminohydroxylation reaction and its asymmetric variant. These reagents were found to be effective under base-free reaction conditions. The scope and limitations of these methods have been explored using a variety of alkenes, among which, trans-cinnamates, in particular, proved to be good substrates.