Phenylphosphonous dichloride

Caution To avoid exposure to toxic phenylphosphonous dichloride vapors, the Grignard reaction should he conducted in a hood. 

Phenylphosphonous dichloride was purchased from Fluka AG or Aldrich Chemical Company, Inc. 

Phenyl-l,3,2 oxazaphospholidine-2-oxides 170a and 170b were formed as a 7 1 diastereomeric mixture in the reaction of (.S Kliphenylprolinol (163) and phenylphosphonic dichloride in the presence of triethylamine (Scheme 47) [78],... 

The reaction between phenylphosphonic dichloride and 2-naphthol in the presence of pyridine to give, ultimately, 2-naphthyl phenylphosphonic acid has been shown to be usefully influenced when DMF is added before the naphthol.40... 

In view of the utility of the aromatic polyesters and the demonstrated effectiveness of the aromatic polyphosphonates as flame retardants, the combination of these two polymers was chosen for this study. In addition, this system provided a composition in which both copolymers and polymer blends could be prepared with identical chemical compositions. The polyesters were prepared from resorcinol with an 80/20 m/m ratio of iso-phthaloyl and terephaloyl chlorides while the polyphosphonates were resorcinol phenylphosphonate polymers. Copolymerized phosphorus was incorporated by replacement of a portion of the acid chloride mixture with phenylphosphonic dichloride. 

The logarithm of the rate coefficient is a linear function of the donicity of dichloromethane, nitromethane, benzonitrile, and acetonitrile (Fig. 16). Deviations in the DN—log fc12 plot are found for solvents with viscosities > 2 cP. The deviation is noticeable for solvents of viscosities between 2 and 3 cP (TMP 2.32 cP, PDC 2.83 cP) and is more pronounced for a solvent of considerably higher viscosity such as phenylphosphonic dichloride (4.10 cP) (Fig. 16). 

The cavitands are essentially synthesized from their resorc[4]arene precursors which are readily obtained by resorcinol condensation with aldehydes. The main feature comes from the different configurations that are expected for this tetrameric species and the relative thermodynamical stability of each isomer, which has been widely investigated by several authors. In addition, the conformational mobility of the resorc[4]arene molecules will depend on substitution at the upper and lower rims [28, 36, 40, 41]. The first attempt to synthesize a phosphorus bridged cavitand was to treat resorc[4]arene la (1, R=CH3) with phenylphosphonic dichloride or phenylphosphonothioic dichloride. Only inseparable isomer mixtures were obtained and isolation of the desired cavitands was not possible [42]. The first isolated phosphorylated resorcinol-based cavitand was described in 1992 by Markovsky et al., who prepared compound D from la and four equivalents of o-phenylenechlorophos-phate in the presence of triethylamine [43, 44]. For this compound, a tautomeric temperature and solvent dependent equilibrium exists between the spirophosphorane structure and the cyclic phosphate form (Scheme 4). 

The esterification of 1,2,5-dithiazepine 68 with phenylphosphonic dichloride in benzene and subsequent hydrolysis gave 122, which upon further esterification with chloromethyl pivalate in MeOH afforded 0-(l,l,4,4-tetramethyl-2,3,5,6,9,10-hexahydroimidazo[2,, 2,5]dithiazepin-9-yl )cthy 10-pi valoyloxy methyl phenylphosphonate 123... 

Thus, reaction of equimolar amounts of 2-phenyl-2,2"-spirobis(l,3,2-benzodioxaphosphole) (3a) 6) and benzhydrol under anhydrous conditions in boiling acetonitrile gave l-benzhy-drylacetamide (40%), bis(benzhydryl)ether (30%) and 2-phenyl-1,3, 2-benzodioxaphosphole (4) which was identified by spectroscopic comparison with an authentic sample prepared from phenylphosphonic dichloride and catechol (10). 

In exploring various synthetic methods for the preparation of 1,2-oxaphospholene 2-oxides we investigated the reaction of diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) with methyl and phenylphosphonous dichloride, which was reported (1) to proceed as shown in eq (1) to give 2,3,3,5-tetramethyl-l,2-oxaphos-phol-4-ene 2-oxide or the corresponding 2-phenyl derivative. 

Chlorination of compound (200) to give 4,6-dichloro-3-methylisothiazolo[5,4-ft]pyridine (203) has been accomplished by using phenylphosphonic dichloride (Equation 14) <90JCS(P1)1477>. 

Lactams, e.g. (26) (67T681), can be chlorinated in the usual manner with phosphorus oxychloride. Phenylphosphonic dichloride is often a preferable reagent in this type of reaction, especially if the reaction requires a relatively high temperature for complete conversion, e.g. for the isoquinoline analogue (27) (75JCS(P1)2190). 

This reaction is conveniently carried out in a 2-1., three-necked flask with 143 g. phenylphosphonous dichloride (0.8 mole), 74 g. absolute ethanol (1.6 moles), 163 g. triethylamine (1.6 moles), and 700 ml. benzene. The yield of water-white product is about 100 g. (63%). It is soluble in most organic solvents and slowly reacts with air it should be stored under nitrogen. Its infrared spectrum has been reported.4... 

The Step 1 product (1.5 mmol) was dissolved in 10 ml benzene at 0°C and treated with phenylphosphonic dichloride (1.7 mmol), lH-tetrazole (8 mg), and N,N-diisopropylethyl amine (3.4 mmol). The mixture was then stirred at ambient temperature and a precipitate isolated after 15 minutes. The mixture was stirred for an additional 12 hours, then treated with 0.1ml methyl alcohol, and the mixture concentrated after an additional 4 hours of stirring. The residue was purified by chromatography with CHCl3/methyl alcohol/NH4OH, 9.5 0.5 0.02, and the product isolated in 89% yield as a mixture of diastereomers. 

Reaction of (A-benzyl-amino) propionic acid 337a and its 3-methyl derivative 337b with phenylphosphonic dichloride in the presence of excess of NEt3 gave the diazocinediones 9a,b, which have a cyclo-/3-dipeptide structure (Equation 13). The reaction was performed under different reaction conditions, that is, changing solvents, temperature, reaction time, and reactant concentration. The best results (54-68% yields) were obtained in benzene at 80°C for 20h. The diazocinediones 9a,b were formed in similar yields at high and low concentrations of the reactant <2001T1883>. 

SYNS PHENYLDICHLOROPHOSPHINE O PHENYL-PHOSPHINE DICHLORIDE PHENYLPHOSPHONOUS ACID DICHLORIDE PHENYLPHOSPHONOUS DICHLORIDE PHENYL PHOSPHORUS DICHLORIDE PHENYL PHOSPHORUS DICHLORIDE (DOT)... 

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