Reaction of 13-Vertex Carborane μ‑1,2-(CH₂)₃‑1,2‑C₂B₁₁H₁₁ with Nucleophiles: Scope and Mechanism

13-Vertex carborane, μ-1,2-(CH2)3-1,2-C2B11H11 (1), reacted with a series of nucleophiles (Nu) to give the cage carbon extrusion products [μ-1,2-(CH2)3­CH­(Nu)-1-CB11H10]−, [μ-1,2-(CH2)2­CH­(Nu)­CH2-1-CB11H10]−, and/or [μ-1,2-(CH2)2­CHCH-1-CB11H10]−, depending on the nature of Nu and the reaction conditions. The key intermediates for the formation of CB11– anions were isolated and structurally characterized as [μ–η:η:η-7,8,10-(CH2)3­CHB­(Nu)-7-CB10H10]− (Nu = OMe, NEt2). The reaction mechanism is thus proposed, which involves the attack of Nu at the most electron-deficient cage boron, followed by H-migration to one of the cage carbons, leading to the formation of the intermediate. Nu-migration gives the products.