solvent and nucleophiles but also for 6, which has gained two hydrogen atoms from the reaction medium. Fortunately, the use of labeled solvent helped to elucidate the origin of 6. Thus when tetrahydrofuran-d8 is the solvent, the 2-chloronaphthalene is 79% d2, 13% dl, and 8% undeuterated. The I3C NMR spectrum was used to establish the position of the deuterium atoms as in 6aa8