A Novel N,P,C Cage Complex Formed by Rearrangement of a Tricyclic Phosphirane Complex: On the Importance of Non-covalent Interactions

摘要

The reaction of Li/Cl P-CPh_3 phosphinidenoid tungsten(0) complex 2 with dimethylcyanamide afforded tricyclic phosphirane complex 4, an unprecedented rearrangement of which led to the novel N,P,C cage complex 6. On the basis of DFT calculations, formation and intramolecular 3+2 cycloaddition of the transient nitrilium phosphane ylide complex 3 to a phenyl ring of the triphenylmethyl substituent to give 4 is proposed. Furthermore, theoretical evidence for terminal N-amidinophosphinidene complex 7, formed by 2+1 cycloelimination from 4, is provided, and the role of the electronic structure and non-covalent interactions of intermediate 7 discussed.