- Contributions to the Chemistry of Boron, 220. - Investigations on Diborylmethanes
-
A convenient synthesis and spectroscopic properties of various organyl-halogen-substituted diborylmethanes (RXB)2CH2 (2a-e, R = Me, Et, iPr, Ph, Mes) are described.Reaction of bis(dichloroboryl)methane (1b) with tBuLi in a 1:2 ratio leads to isomerization of the tert-butyl group, whereas bis(dimethoxyboryl)methane (1a) reacts with 5 equivalents of tBuLi to yield tri-tert-butylborane and lithium di-tert-butylmethyleneborate (9).Borate 9 is characterized NMR-spectroscopically and by derivatization with Me3SiCl.Bis(alkinyl(dialkylamino)boryl>methanes 10a-c are obtained from the bismethanes 5a, b and LiCCPh or LiCCMe, respectively. 10c is characterized by an X-ray crystal structure analysis which allows, for the first time, a direct comparison of an sp- and an sp3-carbon atom bound to the same boron atom.Finally, an almost linear relationship between δ13C of the methylene group and δ11B in diborylmethanes has been detected. - Key Words: Diborylmethanes/ Alkynyl boranes/ Boron carbon NMR coupling fine structure
- Ederer, Bernd,Metzler, Nils,Noeth, Heinrich
-
p. 2003 - 2010
(2007/10/02)
-