Olefins react regioselectively with Boc-NHOH in the presence of Cu(I,II) salts to produce allyl-N(OH)(Boc) derivatives, apparently via the intermediacy of Boc-N=O; yields and rates are dramatically improved by the addition of H2O2. The corresponding allylamine derivatives, allyl-NH(Boc), are formed selectively from Boc-NHOH/olefin with CuBr/P(OEt)(3). (C) 2005 Elsevier Ltd. All rights reserved.