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Comprehensive Summary: Herein, we describe a direct route for the synthesis of 3‐gem‐difluorovinyl lactams through Zn‐mediated reductive hydrodehalogenation. Importantly, by using inexpensive deuterium oxide (D2O), the high value‐added vicinal dideuterated gem‐difluoroalkenes with excellent deuterium (D) incorporation were prepared. Mechanism studies indicated a successive single electron transfer process: the reaction initially undergoes hydrodechlorination to give the intermediate α‐trifluoromethylidene lactams, which are then activated by the in‐situ generated zinc cations and reduced to the desired product via hydrodefluorination. [ABSTRACT FROM AUTHOR]

It is suggested that the abnormal methane IR frequency shift observed in ZnZSM‐5 zeolites is caused by adsorptive interaction of CH4 with particularly strong Zn2+ Lewis sites. Various molecular structures of zinc ion species in high‐silica zeolites are discussed, and it is concluded that increased Lewis acidity of a site is associated with decreased structural stability. It is shown that Zn2+ in zeolite cationic position with distantly placed A1 ions can produce observed shift of vibrational frequencies for adsorbed methane molecule. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 [ABSTRACT FROM AUTHOR]