Patent ID: 6858729

Claim:
A compound of formula I, wherein R 1 and R 2 , which can be the same or different independently of one another, stand for one of hydrogen; halogen; pseudohalogen; a nitrile and/or nitro group; an unsubstituted —NR 3 R 4 , —OR 5 , —PR 3 R 4 and —SR 6 ; —NR 3 R 4 , —OR 5 , —PR 3 R 4 or —SR 6 substituted with an alkyl, aryl, or an hetaryl; or R 1 and R 2 can be a fused carbocyclic or heterocyclic ring; wherein X 1 and X 2 , which can be the same or different independently of one another, stand for one of halogen, alkyl- and aryloxy, or both jointly forming a cycle with the boron atom through an at least bidentate ligand, the bidentate ligand having at least two places to bind a central atom, the ligand having hydroxy and/or carboxylic acid groups and being a diol, a hydroxy carboxylic acid or a dicarboxylic acid that is one of —OC 2 H 4 O—, —OC 3 H 6 O—, glycolate, lactate, tartrate, sylicylate, mandelate, benzilate, 1,2- or 2,3-hydroxynaphthoate, oxalate, malonate, alkylmalonate or dialkymalonate.