Rearrangement Studies with 14C. XXXVIII. Isotopic Scrambling in the Synthesis of Labeled 2-Phenylethyl Triflate

Abstract

2-Phenylethyl triflate (1-OTf) was synthesized by the reaction of AgOTf with 2-phenylethyl iodide (1-I) in cyclohexane as solvent. However, when 1-14C-2-phenylethyl iodide (1-I-1-14C) was used as a reactant, the resulting 1-OTf-14C showed an essentially complete scrambling of the 14C-label over the C-1 and -2 positions. Similar reactions of 1-I-1-14C with AgOTs and with AgOAc gave 1-OTs-14C and 1-OAc-14C with, respectively, about 49 and 11% rearrangement of the label from C-1 and -2.