Synthesis and x-ray crystal structure of the cyclopentadienyl nitrito complex of ytterbium(III), (C 5H 5) 2Yb(NO 2) · THF

Abstract

Cp 2Yb(NO 2) · THF ( 1) (Cp = C 5H 5) was synthesized by the reaction of Cp 2YbCl and NaNO 2 (1:1 molar ratio) in THF at room temperature. It crystallizes in space group Pnma with unit cell dimensions a = 13.5530(3), b = 11.8150(2), c = 9.2790(2) Å, Z = 4, V= 1485.8 Å 3 and D x 1.883 g cm −3. Least-squares refinement based on 1010 unique reflections with I ⩾ 3σ( I) converged to a final R value of 0.023. The ytterbium atom was connected to two η 5-bonded cyclopentadienyls and three oxygen atoms (one from the coordinated THF molecule and other two from the chelate nitrite ligands) in a distorted hexahedral arrangement. The average YbC(Cp) distance is 2.64(2) Å, YbO(THF) and YbO(NO 2) distances are 2.310(7) and 2.388(9) Å, respectively. The title complex loses the coordinated THF molecule readily on heating under vacuum to give dimeric complex [Cp 2Yb(NO 2)] 2 ( 2). Two new complexes have been characterized by elemental analysis and by IR spectroscopy and mass spectrometry.