UC Irvine

Dinitrogen can be reduced by photochemical activation of the trivalent rare earth bis(pentamethylcyclopentadienyl) allyl complexes (η5-C5Me5)2Ln(η3-C3H4R) (Ln = Y, Lu; R = H, Me) to form the (N=N)2− complexes, [(C5Me5)2Ln]2(μ-η2:η2-N2). This demonstrates that productive organolanthanide photochemistry is not limited to complexes of the unusual (η3-C5Me4H)1- ligand found in the heterometallic complexes (C5Me5)2(C5Me4H)Ln and (C5Me5)(C5Me4H)2Ln (Ln = Y, Lu, Dy). Photolytic activation of (C5Me5)2Ln(C3H5) (Ln = Y, La) in the presence of isoprene provides a rare photopolymerization route to polyisoprene. Irradiation of (C5Me5)2Y(C3H4Me) in the absence of other substrates results in the isolation of the corresponding ‘tuckover’ complex, (C5Me5)2Y(μ-H)(μ-η1:η5-CH2C5Me4)Y(C5Me5).