Syntheses of Phosphoryl Chloro- and Bromofluorides and Crystal Structures of POFCl2 and POF2Cl

Abstract A simple procedure for the preparation of phosphoryl chlorofluorides, POFCl 2 and POF 2 Cl, by chlorination of the appropriate potassium fluorophosphates, K 2 PO 3 F and KPO 2 F 2 , respectively, with PCl 5 is described. The analogous bromination with PBr 5 gives POFBr 2 and POF 2 Br. However, due to low yields and high content of impurities, this method is not suitable for the synthesis of the former compound. Both chlorofluorides were crystallized from the melt at low temperatures and their crystal structures were determined by X‐ray diffraction at −153 °C. Distorted tetrahedral molecules of POFCl 2 are only weakly associated through intermolecular O···Cl contacts forming infinite chains similarly as in crystalline POCl 3 . In POF 2 Cl, however, the chains are formed by the O···P contacts, and an additional P–O···Cl bridging leads to their linkage into a double‐chain structure.