Effects of remote N-(tert-butoxycarbonyl) groups on heteroatom directed lithiation at benzylic positions

Article abstract of DOI:10.1016/S0040-4020(01)90188-7

Lithiation of N-BOC-2-methylphenethylamine (6) occurs exclusively at the methyl group whereas lithiation of the phenylpropyl congener (11) is less regioselective. N-BOC-phenylpropylamine (17) is efficiently lithiated at the benzylic position while N-BOC-2