Phosphonous dichloride,

Chemical Designations - Synonyms Phenyl Phosphonous Dichloride, Phenylphosphine Dichloride, Dichlorophenylphosphine Chemical Formula CjHjPClj. 

Synthesis of Phosphonic and Phosphinlc Acids and their Derivatives.-The phosphonium adducts from PCl and alkyl vinyl ethers are converted into the corresponding phosphonic dichlorides by hexamethyldisiloxane. Oxidative phosphorylation of the 1,3-butadienes (53) affords the phosphonic dichlorides (54). 

Treatment of (-)-ephedrine (42) with a variety of aIkyl(aryl)phosphonic dichlorides 106a-d afforded the isomeric pairs of the corresponding 2-alkyl(aryl)-2-oxo-l,3,2 oxazaphospholidines (Scheme 31 and Table 1) [32, 62-65],... 

It is interesting to note that [(E)-2-phenylethenyl]-[018]phosphonic dichloride (116) upon treatment with (-)-ephedrine (42) in the presence of triethylamine afforded an equimolar mixture of (2S,4S,5R)- and (2/ ,4S, 5/ )-2,3-dimethyl-5-phenyl-2-[(E)-2-phenylethenyl]-l,3,2-oxazaphospholidin-2-[180]one 117a and 117b. The two diastereomers were completely separated by flash chromatography and the diastereomer 117b was hydrolyzed with water H20-170 to the corresponding monoester 118 which was finally converted to dihydro-(l,2-dibromo-2-phenyl- 1-ethyl) (R)-160,170,180 phosphonic acid 119 (Scheme 33) [66],... 

The reaction of 2-deoxy-3,4,6-tri-0-methyl-2-methylamino-D-glucopyranose 149 with methyl(phenyl)phosphonic dichlorides (106a-b) or methylthiophosphonic dichloride in benzene in the presence of triethylamine afforded mixtures of four isomers of the corresponding 1,3,2 oxazaphospholidine-2-ones 150, 151 and... 

A rich family of 2-alkoxycarbonyl-l,3,2-oxazaphospholidine-2-oxides 179-181 was prepared from the reaction of camphor derived aminoalcohols 177 and 178 with either methoxycarbonyl phosphonic dichloride or ethyl dichlorophosphite followed by the reaction with methyl bromoacetate. The reaction with aminoalcohol 177a afforded the phosphorus epimers 179 and 180, in ratios from 1/1 to 12/1 depending on the iV-substituent which could be separated easily by column chromatography. The reaction with aminoalcohols 178a-c, however, gave a single epimer 181a-c in each case (Scheme 50) [81]. 

A similar condensation of 177b with chloromethyl phosphonic dichloride gave 2-chloromethyl-l,3,2-oxazaphospholidine-2-oxide 182 which was converted into the cyano derivative 183 by reaction with potassium cyanide in anhydrous dimethyl-sulfoxide (Scheme 51) [82],... 

Benzo derivatives of the pyrido[l,2-f][l,3,2]oxazaphosphorine ring system, [l,3,2]oxazaphosphorino[4,3- ]isoquino-lines 195, 196, were synthesized by the reaction of hydroxyethyl isoquinoline derivatives 183, 184 with phenylphos-phonic dichloride, bis(2-chloroethyl)phosphonic dichloride or phosphoryl chloride. In almost all cases, the products were formed in about a 1 1 diastereomeric ratio. The only exception observed was when phosphoryl chloride was used as the reagent (X = C1) in this reaction one single diastereomer 196 (R2 = R3 = H) was obtained (Scheme 28) <2000JST(554) 119, 2000JOC316>. 

The reaction is performed most simply by the addition of the propargylic alcohol to a solution of the phosphorus halide. Rearrangement of the phosphorus ester proceeds at ambient temperature or with mild heating. When phosphorus trihalides are used, the product can be isolated as the phosphonic dichloride.168169 Aqueous workup provides the phosphonic acid.162 In most instances, however, a dialkyl phosphorochloridite with only a single halogen on phosphorus available for reaction with alcohol has been used.165 170 174... 

Grabiak, R.C., Miles, J.A., and Schwenzer, G.M., Synthesis of phosphonic dichlorides and correlation of their P-31 chemical shifts, Phosph. Sulf, 9,197, 1980. 

The volatility of phosphorus trichloride, ethylphosphonous dichloride and sulphuryl chloride, permit of their quantitative transfer in a high-vacuum system. The conversion of the phos-phonous into the phosphonic dichloride can also be carried out in an enclosed system.5... 

With the same reagents, t-butyl alcohol yields the phosphonic dichloride... 

Other phosphonic dichlorides (45), (46) have been obtained from phosphorodi-chloridites and chlorinated dimethyl ethers.39... 

A convenient synthesis of half-derivatives of thiophosphonic acids starts from the corresponding phosphonic dichloride, with isolation of the trimeric thiophosphonic anhydride (53)44a and subsequent reaction of this with amines and alcohols.446... 

Preparation of Phosphorus Containing Terpolymers. Prepared by substitution of a portion of the acid chloride mixture by a calculated amount of phenyl phosphonic dichloride. The compositions of these polymers are summarized in Table 1. 

Weeks MH Acute vapor toxicity of phosphorus oxychloride, phosphorus trichloride and methyl phosphonic dichloride. Am Ind Hyg Arrowy 25 470-475, 1964... 

Phenylhydrazine Hydrochloride Phenylhydrazinium Chloride Phenyl Hydroxide Phenylmethanol Phenylmethyl Alcohol Phenylmethyl Amine Phenylphosphine Dichloride Phenylphosphine Thiodichloride Phenylphosphonothioic Dichloride Phenyl Phosphonous Dichloride Phenylpropylene 1 -Phenyltetradecane 1-Phenylundecane Phosgene Phosphoric Acid Phosphoric Sulfide... 

Phosphorodipiperididic chloride Phosphonic dichloride, piperi-dino- (8,9) (1498-56-2)... 

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