Bis[benzylbis(dimethylamido)molybdenum] and -tungsten (M.tplbond.M) compounds and their reactions with carbon dioxide and 1,3-diaryltriazenes. A radical difference
1,2-Dibenzyl- and 1,2-diaryltetrakis(dimethylamido)dimolybdenum and -ditungsten compounds: M2R2(NMe2)4 (M.tplbond.M). Structural effects of Me2N-to-M .pi. bonding