Studies on BCl and on the exchange reaction of BCl3 with polyboron fluorides
作者:Jennifer A.J. Pardoe、Nicholas C. Norman、Peter L. Timms
DOI:10.1016/s0277-5387(01)01032-4
日期:2002.3
Gaseous BCl has been prepared at low pressure by reaction of BCl3 with boron at 2000 degreesC or by decomposition of B2Cl4 using either an electric discharge or using flash thermolysis at 1150 degreesC, and then condensed at - 196 degreesC. Reasons are discussed why each method gives BCl capable of generating (Cl2B)(3)BCO when the condensate at - 196 degreesC is treated with CO, but B4Cl4 is only formed from BCl prepared from B2Cl4. The stepwise conversion of (F2B)(3)BCO to (Cl2B)(3)BCO by treatment with BCl3 has been followed by B-11 NMR spectroscopy. Evidence from mass spectrometry and B-11 NMR spectroscopy suggests that reaction of polyboron fluorides, particularly B8F12 and B10F12, with BCl3 yields a new form of B9Cl9 of, as yet, unknown structure which converts slowly to closo-B9Cl9 or closo-B8Cl8 depending on the solvent. (C) 2002 Elsevier Science Ltd. All rights reserved.