Premium
CH Functionalizations by Means of Direct Borane–Hydrocarbon Dehydrogenations and Dehydrocarbonations
Author(s) -
Goldfuss Bernd
Publication year - 2009
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200901368
Subject(s) - electrophile , chemistry , hydrocarbon , boron , methane , medicinal chemistry , carbon fibers , borane , electrophilic substitution , organic chemistry , catalysis , materials science , composite number , composite material
The CH functionalization of methane by means of direct CH borations with BH 3 or MeBH 2 is compared computationally (using the B3LYP/6‐311 ++ G** method) to CH lithiations with LiH or LiMe as well as to other analogue C–metal (Be, Na, Mg, Al) formations. For the borations only, this internal electrophilic substitution at carbon (S E i) relies more on the electrophilicity of boron than on the basicity of the internal base Y, that is, H or Me. Such direct borations of methane are more favored for dehydrogenations than for dehydrocarbonations. Due to decreased electrophilicity, substituents at boron disfavor such borations. Hence, the BH 2 group appears to be most efficient for CH functionalizations by means of direct hydrocarbon borations.