REARRANGEMENTS OF THE METALLODIPHOSPHAPROPENES (ETA-5-C5ME5)(CO)2FEP(SIME3)-P=C(R)(SIME3) (R=SIME3,PH)

Heating of a methylcyclohexane solution of (eta5-C5Me5)-(CO)2FeP(SiMe3)-P=C(SiMe3)2 (1a) gives rise to the insertion of the P=C moiety into the CH bond of a ring methyl group with formation of the chelate complex eta5-C5Me4CH2P-[CH(SiMe3)2]P(SiMe3)Fe(CO)2 (2) which is converted into the pentacarbonylchromium derivative [eta5- 5Me4CH2P[CH-(SiMe3)2]P(SiMe3)[Cr(CO)5]Fe(CO)2] (3). In contrast, a similar treatment of (eta5-C5Me5)(CO)2FeP(SiMe3)-P=C(Ph)(SiMe3) (1b) furnishes the diphosphirane (eta5-C5Me5)(CO)2FeP-C(Ph)-SiMe3)-P(SiMe3) (5). By chromatography of its (CO)5Cr adduct 6, the P-Si bond is hydrolyzed to give the (diphosphirane)-chromium complex [(eta5-C5Me5)(CO)2FeP-C(Ph)(SiMe3)P(H)]-Cr(CO)5 (8). The molecular structures of 3 and 8 are determined by single-crystal X-ray analysis.