The preparation and crystal structure of bis(cyclopentadienyl)(2,6-diphenylphenoxo)bis(tetrahydrofuran)neodymium(III); an unexpected example of formal nine coordination

Reaction of NdCP3 (CP=cyclopentadienyl) with an equimolar amount of 2,6-diphenylphenol (HOdpp) in tetrahydrofuran (thf) yields the formally ninecoordinate [NdCp2(Odpp)(thf)2]. The crystal structure shows a distorted trigonal bipyramidal arrangement of oxygen donor atoms and cyclopentadienyl ring centroids, with the thf oxygens in the axial positions and a twofold axis along NdOdpp bond