| Abstract
| - Mixed-metal cubane-type clusters [{Mo(O)Cl2}{MoCl2(DMF)}(Cp*M)2(μ3-S)4] (M = Ir, Rh) have been prepared, and their stoichiometric reactions with MePhNNH2 as well as the reductive cleavage of MePhNNH2 catalyzed by these clusters have been investigated.
- Reactions of [{Mo(O)(DMF)3}2(μ2-S)2]I2 (1) with an equimolar amount of [(Cp*MCl)2(μ2-SH)2] (M = Ir, Rh; Cp* = η5-C5Me5) and excess [Me4N]Cl in DMF at room temperatureafforded cubane-type clusters with a terminal oxo ligand, [{Mo(O)Cl2}{MoCl2(DMF)}(Cp*M)2(μ3-S)4] (M = Ir (5), Rh (6)), while treatment of 1 with [(Cp‘RuCl)2(μ2-SH)2] (Cp‘ =Cp*, Cp°; Cp° = η5-C5EtMe4) under analogous conditions gave cubane-type clusters withoutoxo ligands, [{MoCl2(DMF)}2(Cp‘Ru)2(μ3-S)4] (Cp‘ = Cp*, Cp° (7‘)). Cluster 5 reacted withMePhNNH2 in DMF at room temperature, yielding the methylphenylhydrazido(2−) cluster[{Mo(NNMePh)Cl2}{MoCl2(DMF)}(Cp*Ir)2(μ3-S)4] (9), which upon treatment with lutidiniumchloride (Lut·HCl) as the source of protons and cobaltocene as the source of electrons producedPhNHMe in considerable yield. Catalytic conversion of MePhNNH2 into PhNHMe throughthe reductive cleavage of the N−N bond by a Lut·HCl/cobaltocene mixture was attained bythe use of the cubane-type clusters as catalyst precursors, which include 5, 6, and theirmixed-chalcogenido analogues [{Mo(O)Cl2}{MoCl2(DMF)}(Cp*M)2(μ3-S)2(μ3-Se)2] (M = Ir,Rh). X-ray analyses have been undertaken for 5, 7‘, and 9 to determine their detailedstructures.
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