Molybdenum diphosphines

Electronic Structure and Spectroscopic Properties of Molybdenum and Tungsten N2, NNH, NNH2, and NNH3 Complexes with Diphosphine Co-Ligands Insights into the End-on Terminal Reduction Pathway of Di nitrogen Felix Tuczek... 

ELECTRONIC STRUCTURE AND SPECTROSCOPIC PROPERTIES OF MOLYBDENUM AND TUNGSTEN N2, NNH, NNH2i AND NNH3 COMPLEXES WITH DIPHOSPHINE CO-LIGANDS INSIGHTS INTO THE END-ON TERMINAL REDUCTION PATHWAY OF DINITROGEN... 

Full details have now appeared of the stereoselective synthesis of 1,5,9-triphosphacyclododecane systems by oxidative liberation from molybdenum and chromium complexes of the macrocycle, obtained by coordination-template controlled reactionsMolybdenum complexes have also been used in the coordination-template dependent synthesis of the macrocyclic P,S system 151. A non-template synthesis of the 14-membered P2S2 macrocycle, 152, isolated in two isomeric forms, has been described. Halogenation of the cyclometallated phosphine 153 leads to a rearrangement, with the formation of the di-phosphinobiphenyl system 154, from which the free diphosphine can be liberated... 

A convenient preparatory method is to form the tertiary phosphine molybdenum hexafluoride complex in methylene chloride at -60°C. On heating such complexes, R3PF2-type compounds are liberated (6.510). Hydrogen fluoride adds to alkylphosphonous dihalides (6.511). Fluorophosphoranes are also obtained from diphosphines (6.538 below), or by halogenation of R2NPF2 -type compounds (7.107). 

The electrodWmical reactions discussed are primarily those which involve the binding and transformation of molecular nitrogen at robust molybdenum and tungsten tertiary diphosphine sites of the type trans - M(Ph2PCH2CH2PPh2)2l (M = Mo or W ). Such sites provide a stable... 

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