Reaction of octakis(dimethylamino)tetraphosphonitrile with antimony trifluoride

Abstract

A series of 14 non-germinally substituted dimethylaminofluorotetraphosphonitriles, P₄N₄F_n(NMe₂)_{8 –n} where n= 1,2(four isomers), 3(three isomers), 4(three isomers), and 5(three isomers), has been prepared by the reaction of P₄N₄(NMe₂)₈ with antimony trifluoride. The tetra- and penta-fluorides are identical with those obtained from the fluorination of P₄N₄Cl₄(NMe₂)₄ but five new compounds have been separated and assigned structures from g.l.c., ¹H and ¹⁹F n.m.r. data. The reaction mechanism is thought to be similar to that discussed previously and involves co-ordination of antimony trifluoride to the most basic ring nitrogen atom rather than to an amine substituent. Fluorination follows a non-geminal path with a tendency to form larger amounts of trans- rather than cis-isomers.