Preparation of Difluorophosphonoacetic Acid and Its Derivatives
The preparation of ethyl difluoro(diethoxyphosphinyl)acetate (1) has been effected by the acylation of zinc bromide with ethyl chloroformate in the presence of a catalytic amount of cuprous bromide.Similarly prepared were ethyl difluoro(diethoxyphosphinyl)pyruvate (2) and N,N-diethyldifluoro(diethoxyphosphinyl)acetamide (3).Bromotrimethylsilane selectively reacted with 1 to yield ethyl difluoroacetate (9).The remaining ethyl carboxylic ester of 9 reacted with iodotrimethylsilane to produce trimethylsilyl difluoroacetate (10), which was subsequently hydrolyzed to yield difluorophosphonoacetic acid (8).The phosphonate 9 was gently chlorinated to yield ethyl difluoro(dichlorophosphinyl)acetate (11).
Burton, Donald J.,Sprague, Lee G.
p. 1523 - 1527
(2007/10/02)
Syntheses of some fluorine-containing halomethanephosphonate and methylenebisphosphonate esters
The Michaelis-Becker reaction between diethyl sodiophosphite and either of the halofluoromethanes CF2Cl2 and CF3Br gives tetraethyl difluoromethylenebisphosphonate.By contrast, the corresponding reaction with CFCl3 gives not only diethyl dichlorofluoromethanephosphonate but also teraethyl prophosphate as the major product.Diethyl dichlorofluoromethanephosphonate, readily prepared by a normal Arbusov reaction from+ CCl3F, reacts with diethyl sodiophosphite to give tetraethyl fluoromethylenebisphosphonate thereby providing a simple efficient, and inexpensive synthesis of this useful material.
Blackburn, G. Michael,Taylor, Graham E.
p. 55 - 62
(2007/10/02)
More Articles about upstream products of 113161-60-7