Trichloromethylphosphonic acid

X-Ray analy.ses have been performed on salts of diphenyl phosphoric, phenylphosphonic, and trichloromethylphosphonic acids " phosphorylated urea and thiourea derivatives phenyl[[ -acetyloxy(4-nitrophenyl)]methyl]phosphinic acid ... 

Perchloric acid Phosphomolybdic acid Phosphorus oxychloride Phosphorus pentachloride Phosphorus trichloride y-Picoline Polyphosphoric acid Potassium silicate Rhodium Selenium Selenium dioxide Silica gel Silver oxide (ous) Sodium borohydride Sodium silicate Strontium carbonate Sulfur dioxide Tantalum Tellurium Tetraisopropyl di (dioctylphosphito) titanate Titanocene dichloride Trichloromethylphosphonic acid Tristriphenylphosphine rhodium carbonyl hydride Tungsten carbide Vermiculite Ytterbium oxide Zinc chloride Zinc dust Zinc 2-ethylhexanoate Zirconium potassium hexafluoride... 

Trichloromethylphosphonic acid dichloride added drop wise to an ice-cooled stirred suspension of adenosine in triethyl phosphate, stirred 20 hrs. at 0-5 , treated with water, and the product isolated as the ammonium salt adenosine 5 -trichloromethylphosphonate NH4 salt (Y 81-93%) dissolved in dimethylform-amide, 1 N K-/er/-butoxide soln. added, and kept 20 hrs. at 20 adenosine 3, 5 -cyclic phosphate (Y 80%). F. e. s. R. Marumoto, T. Nishimura, and M. Honjo, Chem. Pharm. Bull. 23, 2295 (1975). 

Alkyl esters of phosphonous and phosphinous acid also react readily y with carbon tetrachloride, while analogous aryl esters, e.g., EtP(OPh)2, are resistant even at 160° (152,173). The reaction of bromotrichloro-methane with triethyl phosphite, which occurs smoothly at 80° to furnish dialkyl trichloromethylphosphonate in excellent yield (99%), is light catalyzed. Chloroform is unchanged in the presence of triethyl phosphite (98,156) even under drastic conditions, and diethyl dichloro-methylphosphonate is not produced unless a free radical initiator is present (118). 

Reactions of Phosphonic and Phosphinic Acids and their Derivatives.—Diethyl trichloromethylphosphonate is a useful reagent for the preparation of ethyl esters of carboxylic acids, even in those cases with considerable steric hindrance the yields are very high. ... 

Triethyl phosphate Phosphonic acid monoesters from phosphonic acid dichlorides Nucleoside 5 -trichloromethylphosphonates... 

Esterification.—iVAWW -Tetramethylchloroformamidinium chloride, which is readily prepared from iVAWW -tetramethylurea and oxalyl chloride, is an efficient reagent for the esterification of carboxylic acids with alcohols yields of between 66 and 97% are obtained, and the method has also been applied to macrolide synthesis. A modified one-pot procedure for the esterification of carboxylic acids, using phenyl dichlorophosphate-dimethylformamide complex, has appeared. A simple method of activation of carboxylic acids, using methanesulphonyl chloride and triethylamine followed by addition of the alcohol and 4-dimethylaminopyridine, leads to esters in 57— 96% yield for thirteen examples. 0-Methylcaprolactim reacts with carboxylic acids to give methyl esters in 73—91 % yield for seven examples and 2-iodoethyl esters are prepared from acyl chlorides, ethylene oxide, and sodium iodide. Transesterification, catalysed by titanium(iv) alkoxides, provides an effective method for synthesis of esters. Diethyl trichloromethylphosphonate reacts with carboxylic acids to give ethyl esters via transesterification, in 52 to 98 % yield. ... 

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