Novel triosmium cluster complexes with rod-like molecular geometry. Syntheses and crystal structures of [Os3(µ-H)2(CO)9(µ3-CNC5H4CHNC6H4OC16H33)] and [Os3(µ-H)(CO)10(µ-NC5H3CHNC6H4OC16H33)]

Abstract

The reaction of [Os₃(µ-H)₃(CO)₉(µ₃-CCl)] with 1 equivalent of 1,8-diazabicyclo[5.4.0]undec-7-ene in the presence of a 10-fold excess of NC₅H₄(CHNC₆H₄OC₁₆H₃₃-p)-4 in CH₂Cl₂ at room temperature gave [Os₃(µ-H)₂(CO)₉(µ₃-CNC₅H₄CHNC₆H₄OC₁₆H₃₃)]1 in 40% yield. The electronic absorption spectra of 1 in a series of organic solvents show significant negative solvatochromic shifts. Treatment of the activated cluster [Os₃(CO)₁₀(NCMe)₂] with the same Schiff base in CH₂Cl₂ readily afforded the ortho-metallated cluster complex [Os₃(µ-H)(CO)₁₀(µ-NC₅H₃CHNC₆H₄OC₁₆H₃₃)]2 in 72% yield. Crystal structure analyses of 1 and 2 revealed that they both exhibit an interesting rod-like molecular geometry.