Facile hydrosilylation of norbornadiene by silanes R3SiH and R2SiH2 with molybdenum catalysts

Photochemically activated [Mo(CO)6] and [Mo(CO)4(η4-nbd)] have been demonstrated to be very effective catalysts for hydrosilylation of norbornadiene (nbd) by tertiary (Et3SiH, Cl3SiH) and secondary (Et2SiH2 and Ph2SiH2) silanes to give 5-silyl-2-norbornene, which under the same reaction conditions transform in ring-opening metathesis polymerization (ROMP) to unsaturated polymers and to a double hydrosilylation product, 2,6-bis(silyl)norbornane. The yield of a particular reaction depends very strongly on the kind of silane involved. The reaction products were identified by means of chromatography (GC–MS) and 1H and 13C NMR spectroscopy. In photochemical reaction of [Mo(CO)4(η4-nbd)] and Ph2SiH2 in cyclohexane-d12, η2-coordination of the SiH bond to the molybdenum atom is supported by 1H NMR spectroscopy due to the detection of two equal-intensity doublets with 2JHH = 5.4 Hz at δ 6.12 and −5.86 ppm.

Photochemically activated [Mo(CO)6] and [Mo(CO)4(η4-nbd)] have been demonstrated to be very effective catalysts for hydrosilylation of norbornadiene (nbd) by tertiary (Et3SiH, Cl3SiH) and secondary (Et2SiH2 and Ph2SiH2) silanes to give 5-silyl-2-norbornene, which under the same reaction conditions transform in ring-opening metathesis polymerization to unsaturated polymers and to a double hydrosilylation product, 2,6-bis(silyl)norbornane.Figure optionsDownload as PowerPoint slide