Remarkable product diversity in the "self-organized" reaction of deprotonated acetonitrile with chlorophosphines.

ABSTRACT

This study examined the reaction of in situ deprotonated acetonitrile with different chlorophosphines ClPR(2) (5a-d) to find new nitrile functionalized bis(diphenylphosphino)methane (dppm) ligands. Depending on the steric and electronic demand of the phosphines, very different and unexpected products (1b, 6, 9b and 11) were found. In the case of aryl-substituted phosphines (ClPPh(2) (5a) and ClPMes(2) (5b)), bis(diarylphosphino)acetonitrile compounds (1a and 1b) were found. Introduction of alkyl substituents at the ClPR(2) fragment (R = (t)butyl (5c) and cyclohexyl (5d)) changes the overall reaction behavior drastically. A new heteropentafulvene type structure (6), a P/N-disubstituted acetylene (9), and a P-substituted 3-amidocrotononitrile species (11) were found. Considering the experimental simplicity of these three-component reactions, these products are complex and their formations are highly organized. Most compounds were characterized by X-ray diffraction, NMR spectroscopy, and elemental analysis.