Difluorophosphite

Methyl difluorophosphite has been prepared by the fluorination of CH3POCI2 with SbFs. A more satisfactory route is the direct reaction of PF3, alcohol, and a base.2 

Standard high-vacuum techniques are used throughout.Phosphorus trifluoride can be obtained from Ozark-Mahoning Co. 

In a typical experiment, a 2000-ml bulb equipped with a stopcock is attached to the vacuum system by a standard-taper connection. The bulb is thor- 

Inorganic Syntheses, Volume XVI Edited by Fred Basolo Copyright 1976 by McGraw-Hill, Inc. 

After 2 hr at room temperature, the mixture is frozen at — 196° and allowed to warm slowly, while its volatile contents are distilled through U tubes maintained at —64° (chloroform slush), —140° (cooled 30-60° petroleum ether), and — 196° (liquid nitrogen). White solids remain behind in the reaction vessel. An unidentified oil at — 64° and 5.2mmoles of PF3 at — 196° are discarded. The desired PF2OCH3 (84 mmoles) is found at —140°. The yield, based on consumed PF3, is 62%. 

---

Methyl chlorofluorophosphite, 4 141 analysis of, 4 143 Methyl dichlorophosphite, 4 63 Methyl difluorophosphite, 4 141 analysis of, 4 143 Methylgermanium oxide, 3 67 Methylgermanium sulfide, 3 67 Methylgermanium triiodide, 3 64 analysis of, 3 66... 

III) fluoride below 10° and under a pressure of 50 mm. to produce methyl chlorofluorophosphite and methyl difluorophosphite. 

Methyl difluorophosphite is very readily obtained by the action of antimony(III) fluoride on the dichloro ester. The intermediate, partially fluorinated chlorofluoro ester is produced in appreciable yields only under carefully controlled conditions. Although the conditions outlined below, i.e., low temperature, low pressure, and slow rate of addition of fluorinating agent, favor the formation of the chlorofluoro ester, a mixture results, and the yield of the chlorofluoro ester is low compared to that of the difluoro.1... 

The mixture of reaction products is fractionally distilled in a modified Dufton column as described in synthesis 45. The yields based on methyl dichlorophosphite are chloro-fluorophosphite, about 8%, and difluorophosphite, about 40%. 

Samples of the ehlorofluorophosphite are collected in glass ampoules of approximately 1 ml. capacity, which are then sealed and weighed.2 These samples are hydrolyzed in 125 ml. of solution containing sodium hydroxide in slight excess. The difluorophosphite is most conveniently sampled as a gas in a weighing bulb of 500 ml. capacity (AB, Fig. 16, synthesis 45).8... 

FeCl. catalyzes the reactions between butyl difluorophosphite and 94... 

During an investigation of the chemistry of allyl difluorophosphite, a number of complexes containing the difluorophosphonate group, e.g. [Pt-(PF20)4]2 and [Pd(PF20)4]2, were isolated.312... 

The reaction of the octamethyl silyl ether of resorcarene 2 with four equivalents of PF2CI afforded chiral C4-symmetric tetrakis-difluorophosphites compare Reference 329b. 

Difluorophosphites are colorless, volatile liquids with unpleasant smells which do not rapidly attack glass in the absence of moisture, but are violently hydrolyzed by water. Monofluorophosphites, in general, are less rapidly hydrolyzed. Difluorophosphites fail to add sulfur even under forcing conditions (136) however diethylfluorophosphite (EtO)2PF is oxidized to a phosphorofluoridothiolate with alkylsulphenyl chlorides (260). The reaction of difluorophosphites with chlorine or... 

Other examples of modification in the Michaelis-Arbuzov reaction in the formation of phosphorus-carbon bonds in compounds other than esters are reactions between dichlorophosphites " or difluorophosphites and organic halogen-containing compounds in the presence of iron(III) chloride (reactions 2 and 3). A similar reaction takes place with diethyl fluorophosphite A further variation is that of the photoinitiated reaction, a... 

A number of difluorophosphites react with borane, and it has been shown that their base strengths in this reaction are in the sequence... 

---