The α-chiral secondary and tertiary benzylic carbocations 19− 30 were generated from the corresponding benzylic alcohols 1, 2, and 5− 14 by treatment with FSO3H or FSO3H/SbF5 in SO2ClF as the solvent at− 70° C and characterized by one-and two-dimensional NMR spectroscopy. Coupling constants and NOESY measurements suggest a preferred conformation in which the α-hydrogen atom occupies the 1, 3-allylic-strain position and ...
