title: Reaction of 13-vertex carborane μ-1,2-(CH2)4-1,2-C2B11H11 with nucleophiles: linkage effect on product formation.
abstract: The length of C,C'-linkage has a great influence on the reactivity of 13-vertex carboranes. Reaction of 1,2-(CH2)4-1,2-C2B11H11 (1a) with Et2NH gave a 1:1 adduct nido-7-NEt2H-μ-1,3-(CH2)4-1,3-C2B11H11 (2). Compound 1a reacted with Me2NLi or Et2NLi to afford nido-[9-Nu-μ-7,8,10-(CH2)4CCH-B11H10](-) (Nu = NMe2, [3](-); Nu = NEt2, [4](-)). Complex [4](-) was also obtained by deprotonation of 2. Treatment of 1a with MeOH/base generated nido-[3-OMe-μ-1,2-(CH2)4-1,2-C2B11H11](-) ([5](-)) at room temperature, which was converted to nido-[μ-7,8-(CH2)4CHB(OMe)2-7-CB10H11](-) ([6](-)) upon heating in the presence of Et3N. Complex [6](-) was oxidized by H2O2 to the corresponding alcohol [μ-7,8-(CH2)4CHOH-7-CB10H11](-) ([7](-)) or hydrolyzed to the boronic acid [μ-7,8-(CH2)4CHB(OH)2-7-CB10H11](-) ([8](-)). Reaction of 1a with (4-MeC6H4)SNa produced a CB11(-) anion closo-[μ-1,2-(CH2)4CHS(4-MeC6H4)-1-CB11H10](-) ([9](-)). The above complexes were fully characterized by (1)H, (13)C, and (11)B NMR spectroscopic data and elemental analyses. Molecular structures of 1-[7](-) and [9](-) were further confirmed by single-crystal X-ray analyses.
authors: Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors: Jian
authors: J
authors: Zhang
authors: Zuowei
authors: Z
authors: Xie