Weber L, Kaminski O, Stammler H-G, Neumann B, Romanenko VD. Synthese und Strukturbestimmung von 1-Metallo-1,2-Dihydrophospheten (η5-C5Me5)(CO)2M-PCH(E)-C(E)=C-NMe2 (M = Fe, Ru; E = CO2Me, CN). Zeitschrift für Naturforschung. B. 1993;48(12):1784-1794.The metallo-phosphaalkenes ([eta]5-C5Me5)(CO)2M-P=C(NR2)2 (4a,b,5) result from the reaction of the corresponding bromo compounds ([eta]5-C5Me5)(CO)2MBr with Me3Si-P=C(NR2)2. The complexes 4a and 5a are cleanly converted into the 1-metallo-1,2-dihydrophosphetes ([eta]5-C5Me5)(CO)2M-PCH(E)-C(E)=C-NMe2 (10 a-c) (M = Fe, Ru; E = CO2Me, CN) by treatment with equimolar amounts of dimethyl fumarate or fumarodinitrile, respectively. The products 4a, b, 5 and 10 a-c have been characterized by elemental analysis as well as by spectroscopic data (IR, 1H, 13C, 31P NMR, MS). The molecular structures of 4a and 10a have been determined by single crystal X-ray analysis
