THIA- AND SELENA-ARACHNO-UNDECABORANE 6,7-MU-(CH3E)B10H13 - CRYSTAL STRUCTURE OF ARACHNO-6,7-MU-(CH3SE)B10H13 - THEORETICAL INVESTIGATIONS OF THE MOLECULAR STRUCTURES AND B-11 NMR SHIFTS OF ARACHNO-6,7-MU-(CH3E)B10H13 [German]

摘要

The reaction of B10H14 With (CH3)(2)S yields with loss of H-2 the base adduct 6,9-[(CH3)(2)S](2)B10H12. Although an analogous reaction between B10H14 With disulfanes or diselenanes was expected to produce 6,9 bridged dichalcogen derivatives, (CH3)(2)S-2 failed to react, even under reflux conditions. Trisulfane (CH3)(2)S-3 does react, but the pathway is different and leads to (CH3S)B10H13 2 without loss of Hz. Unlike of (CH3)(2)S-2, (CH3)(2)Se-2 yields (CH3Se)B10H13, 3. Both 2 and 3 are formed by substitution of a bridging hydrogen and could be obtained in pure form and characterized NMR spectroscopically. A single crystal X-ray structure analysis also was performed on 3 (space group P2(1)/c). The molecular structures of 2 and 3 were optimized at the MP2 level and B-11 NMR shifts were computed at the IGLO-SCF, GIAO-SCF and GIAO-B3LYP levels of theory. [References: 25]