B–H bond iodination of polyhedral dimolybdaborane and dimolybdathiaborane clusters

Abstract

Reaction of [Cp∗MoCl₄ (Cp∗ = η⁵-C₅Me₅) with excess of [LiBH₄·thf] followed by pyrolysis with NaI yielded B–I inserted [(Cp∗Mo)₂B₅H₉−_nI_n], 1–3 (1: n = 1; 2: n = 2; 3: n = 3). In parallel to the formation of 1–3, the reaction also produced known [(Cp∗Mo)₂B₅H₉] and [(Cp∗Mo)₂ (μ-I)₄] in good yields. Under the similar reaction conditions, dimolybdathiaborane [(Cp∗Mo)₂B₄H₄S₂] yielded iodine substituted dimolybdathiaboranes, [(Cp∗Mo)₂B₄S₂H₄−_nI_n], 4 and 5 (4: n = 2; 5: n = 3) in good yields. All the new compounds have been characterized in solution by IR, ¹H and ¹¹B NMR as simple substituted derivatives of [(Cp∗Mo)₂B₅H₉] and [(Cp∗Mo)₂B₄H₄S₂]. The solid state structures were established unambiguously by crystallographic analysis of compounds 1–5.