Chloroacetone phosphate

When performed in ether at —70 °C containing HCl, the reaction between triethyl phosphite and either chloral or bromoacetone affords higher yields of the a-hydroxyphosphonates (34), relative to vinyl phosphate, than are normally obtained. The rate-determining step in the formation of the phosphonate (35) from chloroacetone and dimethyl hydrogen phosphonate appears to be the tautomerism of dialkyl phosphonate to phosphite. ... 

Sal keeva et al. studied the reactions of ethyl and /-butyl phosphorodiamidites with chloroacetone, bromoacetone, and a-chloroethyl acetate. The reaction pathway is determined by the structure of the intermediate quasiphosphonium compound responsible for the formation of the Arbuzov products as well as for the occurrence of the anomalous reaction yielding vinyl phosphate (Perkow product).26 The yield of the Arbuzov product increases from chloroacetone to bromoacetone, because the anions of low basicity are more rapidly ionized, which facilitates the formation of the ionic form of the intermediate. Also /-butyl phosphorodiamidite forms via Arbuzov reaction as the major product, because the second stage of the S l reaction is accelerated.26... 

The addition of hydrogenphosphonates to chloroketones, and also to other mono halo-genated carbonyl compounds, is aided by the presence of AI2O3, yields of 78-96% being achievable. However, reactions between dialkyl or diphenyl hydrogenphosphonates and chloroacetone " ", 5 m-dichloroacetone or a ym-dichloroacetone " do occur in the absence of a catalyst when mixtures of reactants are heated to 100-120 °C the products are the phosphonates 173 (R = H or Cl). Aryl trichloromethyl ketones are mon-odechlorinated by the action of trialkyl phosphites or dialkyl hydrogenphosphonates and both further dechlorination and the formation of phosphate esters have been... 

The nature of any solvent and the reaction temperature can also be of some importance. For the reaction between trimethyl phosphite and bromoacetone, carried out in diethyl ether at 30 °C, in MeOH or thf at 60 °C or in the absence of a solvent at 110-120 °C the yields of dimethyl (2-oxopropyl)phosphonate were 35, 28, 55 and 45%, whilst those of dimethyl ethenyl phosphate were 30,55,30 and 55%, respectively The proportion of oxoalkylphosphonate to enol phosphate for the reaction between triethyl phosphite and bromoacetone at 150 °C is 20 80, and this ratio is reversed if the reaction is carried out in boiling diethyl ether. Sometimes a change in both solvent and halogen produces a pronounced beneficial effect with regard to phosphonate formation thus the 80 20 advantage just noted for bromoacetone in diethyl ether is raised to 90 10 for chloroacetone at 150 °C, but for iodoacetone in boiling diethyl ether it is only 10 90 ... 

In a further interesting study , the silyl phosphite 515 reacted with haloacetones in the absence of a solvent to give the products 516-518. The main product from chloroacetone was the silyloxyphosphonate 518 (70%) accompanied by a small amount (14%) of the enol phosphate 517, but with the change of X from Cl to Br to I, 518 was eliminated entirely, and the proportion of 517 increased for X = Br but then decreased for X = I the amount of (2-oxopropyl)phosphonate (516) increased from 0% (X = Cl) to 24% (X = Br) to 41% (X = I). In hot MeCN the yield of phosphonate increased to 50% with little change in the amount of enol phosphate, but in MeCN at room temperature or below, the amounts of 516 and 517 both decreased, but there was no formation of the corresponding 491 (X = H). 

Caustic potash Chloric acid Chlorine, dry Chloroacetic acid Chloroacetone Chloroform Chlorosilanes Chlorosulfonic acid Chromic acid Chromic chloride Chromic fluorides Chromic hydroxide Chromic nitrates Chromic oxides Chromic phosphate Chromic sulfate Coconut oil Cod liver oil Coke oven gas Copper carbonate Copper chloride Copper cyanide Copper nitrate Copper oxide Copper sulfate Corn oil Coconut oil Cresylic acid Crude oil Cutting oils Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Denatured alcohol Detergent solution Dex train Dextrose Diacetone Diallyl ether Diallyl phthalate Dichloroacetic acid Dichloroaniline o-Dichlorobenzene Dichloroethane Dichloroethylene Dichloromethane Dichlorophenol Diesel oil... 

To 0.20 mol triethyl phosphite heated to 120°C was added 0.20 mol chloroacetone in small portions. After completion of the addition, the mixture was stirred at 120°C for 1 h, then the temperature was raised to 170°C for an additional hour, whereupon 47% of diethyl 2-propenyl phosphate was distilled, b.p. 64°C at 0.9 mmHg. 

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