Communications to the Editor 1419 product sublimed into a trap cooled by liquid nitrogen and was found to be more than 95% pure by 13C NMR.The structure proof for 1 is based on the mass spectrum1 la (m/e 146 (M+)), the IR spectrum1 la (v 3040 cm-1), the NMR spectrum ((CeDe) 2.36-1.06 (multiplet and two distinctive doublets at 2.12 and 1.08, J = 4 Hz1 lb)), and the 13C NMR spectrum ((C6D6) b 64.4 (d,