1.
Angew Chem Int Ed Engl
; 47(4): 768-70, 2008.
Article
in English
| MEDLINE
| ID: mdl-18058969
2.
Org Biomol Chem
; 4(17): 3297-302, 2006 Sep 07.
Article
in English
| MEDLINE
| ID: mdl-17036118
ABSTRACT
N-Methyl and N-n-butyl-2-(2-boronophenyl)benzimidazoles are accessed from the corresponding mono-N-alkyl-ortho-phenylenediamines, either using a polyphosphoric acid-mediated cyclisation with ortho-bromobenzoic acid, or preferably using an Oxone-mediated cyclisation of the corresponding aldehyde, followed by a lithium-exchange and borylation sequence. The resulting boronic acids show unusual physical and chemical properties, as shown by 11B NMR and X-ray crystallography.