Synthesis, properties and structures of methyldiphenylphosphonium 1-indenylide, 1-C9H6PMePh2, and its chiral tricarbonylchromium(0) complex Cr(η5-1-C9H6PMePh2)(CO)3

The hitherto unknown indenyl-derived ylide, methyldiphenylphosphonium 1-indenylide, 1-C9H6PMePh2 (1) and its chromium(0) complex, Cr(η5-1-C9H6PMePh2)(CO)3 (2) have been synthesized and characterized spectroscopically and crystallographically. The structures and properties of 1 and 2 are compared with those of the analogous C5H4PMePh2 and its chromium complex, Cr(η5-C5H4PMePh2)(CO)3. Compound 2, obtained as a racemic mixture, exhibits planar chirality resulting from coordination of the prochiral aromatic ligand.