Molybdenum complexes Chatt cycle

It is often assumed that certain features of this original Chatt cycle have been explicitly demonstrated, that some of the intermediates invoked have been isolated or at least spectroscopically observed and that some of the elementary transformations of the sequence have been demonstrated [15, 32]. While examples of these phosphine-supported molybdenum and tungsten N2H and NH complexes have been thoroughly characterized (except perhaps an N2H species. 

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