| 摘要 |
Process for the preparation of 6H-dibenz-[c,e][1,2]-oxaphosphorin-6-one of the formula <IMAGE> in which R<1> and R<2> are identical or different and represent halogen, or an alkyl or alkoxy group having 1 to 6 carbon atoms and a and b are identical or different and represent 0, 1, 2 or 3, by reacting a 6-chloro-(6H)-dibenz-[c,e][1,2]-oxaphosphorine of the formula <IMAGE> in which R<1>, R<2>, a and b have the abovementioned meanings, with water in a molar ratio of 1:1 at 50 to 250 DEG C, if appropriate in the presence of a solvent, and removing gaseous hydrogen chloride to the extent in which it is formed. |
