Collect. Czech. Chem. Commun. 2008, 73, 1681-1692

Polyfluoroorganoboron-Oxygen Compounds. 7. Studies of Conversion of [(C6HnF5-n)B(OMe)3]- Into [(C6HnF5-n)2B(OMe)2]- (n = 0, 1)

Nicolai Yu. Adonina,*, Vadim V. Bardinb and Hermann-Josef Frohnc

a G. K. Boreskov Institute of Catalysis, Siberian Branch Russian Academy of Sciences, Lavrentjev Ave. 5, 630090 Novosibirsk, Russia
b N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch Russian Academy of Sciences, Lavrentjev Ave. 9, 630090 Novosibirsk, Russia
c Department of Chemistry, Inorganic Chemistry, University of Duisburg-Essen, Lotharstr. 1, D-47048 Duisburg, Germany


Conversion of salts Li[(C6HnF5-n)B(OMe)3] (n = 0, 1) into (Li·DME)[(C6HnF5-n)2B(OMe)2] was studied in dichloromethane-DME solution. The observed rate constants k decrease from (21.4 ± 0.9) × 10-3 l mol-1 s-1 (Li[C6F5B(OMe)3]) over (6.99 ± 0.11) × 10-3 l mol-1 s-1 (Li[(2,3,5,6-C6HF4)B(OMe)3]) to (2.94 ± 0.05) × 10-3 l mol-1 s-1 (Li[(2,3,4,6-C6HF4)B(OMe)3]), while Li[(2,3,4,5-C6HF4)B(OMe)3] does not undergo any transformation. Hydrolysis of (Li·DME)[(C6HnF5-n)2B(OMe)2] leads to corresponding borinic acids, whereas treatment of them with aqueous solution of M[HF2] (M = Bu4N, K) acidified with HF results in M[(C6HnF5-n)2BF2] in high yields.

Keywords: Polyfluorophenyltrimethoxyborate; Bis(polyfluorophenyl)dimethoxyborate; Polyfluorobenzene derivatives; 19F NMR spectroscopy; Organoborate salts.

References: 22 live references.