Synthesis and structure of heterometallic clusters of early transition metals

Department of Chemistry, Indian Institute of Technology Madras, Chennai-600 036, India

E-mail: sghosh@iitm.ac.in

Univ Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, F-35000 Rennes, France

Manuscript received online 15 September 2019, accepted 19 September 2019

In continuation of our recent studies on the reactivity of [(Cp*Nb)₂ B₄ H₁₀O], I with metal carbonyls, we have carried out its reactivity with [Fe₂ (CO)₉ ] that led to the formation of [(Cp*Nb)₂ B₂ H₄O{H₂ Fe₂ (CO)₆ BH}], 1. Compound 1 is a heterometallic boride cluster in which [Nb₂ Fe₂ ] core describes a butterfly framework with one boron atom lying in a semi-interstitial position. Further, in an attempt to isolate the heterometallic metallaboranes of group 4, we have performed the thermolysis reaction of [Cp₂ Hf(BH₄ )₂ ] with [Cp*IrB₃ H₉ ] that led to the formation of arachno-[(Cp₂ Hf)(Cp*Ir)B₃ H₉ ], 2, analogous to [(Cp₂ Zr)(Cp*Ir)B₃ H₉ ]. Compounds 1 and 2 have been characterized by mass spectrometry, ¹H, ¹¹B and ¹³C NMR spectroscopy and the structural types were unequivocally established by crystallographic analysis.