Reaction of C6F5Br with Li[1-R-1,2-closo-C2B10H10] readily gives compounds 1-(4-BrC6F4)-2-R-1,2-closo-C2B 10H10 [R=Me (1), Ph (2), But (3)]. Compounds 1-3 were characterised by NMR spectroscopy and single crystal X-ray diffraction studies. A significant lengthening of the Ccage-Ccage connectivity is seen as the steric demands of the cage bound substituents increase, from 1.712(7) Å in 1 to 1.736(7) and 1.743(8) Å in 2 and to 1.761(6) Å in 3, the last being the longest Ccage-Ccage distance recorded for a carbaborane with alkyl or aryl substituents. © Elsevier Science Ltd.
|Number of pages||8|
|Publication status||Published - 28 May 1999|