Diphenylphosphinic chloride

Diphenylphosphinic chloride reacts with the superoxide anion radical (Oi ) in CH3CN under mild conditions to form the diphenylphosphinic peroxy radical intermediate 77, which shows strong oxidizing abilities in the epoxidation of alkenes, oxidation of sulfoxides to sulfones, desulfurization of thioamides to amides and oxidation of triphenylphos-phines to triphenylphosphine oxide in good to excellent yields (equation 105). ... 

Diphenylphosphinic amide (I) can be readily prepared in 701 yield from diphenylphosphinic chloride by a modified procedure described by Russian workers 31. 

A previous description of the synthesis of (CH3)3SiP(C6H5)2 in Inorganic Syntheses1 involves the initial preparation of sodium diphenylphosphide from diphenylphosphinous chloride. This method of preparation of the diphenylphosphide anion requires rigorous conditions and long reaction times. At least two other easier methods of preparation of the diphenylphosphide anion (lithium counterion) are known. One synthesis uses diphenyl-phosphine and n-butyllithium2 as reactants, whereas the second uses triphenylphosphine and elemental lithium.3,4 The second method is described here. 

The Step 1 product (5.10 mmol) dissolved in THF cooled to — 15°C was treated dropwise with diphenylphosphinic chloride (6.63 mol), then stirred 20 minutes and further treated with Al-methyl morpholine (6.375 mmol), and stirred additional 20 minutes. (/ )-0-(2,2-dimethyl-[l,3]dioxolan 4-yl methyl )-hydroxylamine (5.1 mmol) was added and the mixture stirred for 1 hour. Additional At-methyl morpholine (6.37 mmol) was added and the mixture stirred 12 hours at ambient temperature and was then concentrated. The residue was diluted with EtOAc, washed twice with saturated NaHC03 solution, once with brine, dried using Na2S04, and reconcentrated. The residue was purified by chromatography with silica gel using hexane/EtOAc, 4 1, and the product isolated in 68% yield. 

Dimethylhydrazino)diphenylphosphine may be prepared by the action of wnsym-dimethylhydrazinet on diphenylphosphinous chloride in benzene at temperatures just below room temperature. A 2 1 mol ratio provides an extra mol of the free base to act as a hydrogen chloride acceptor. The M7Wi/m-dimethylhydrazinium chloride, which is only very slightly soluble in benzene, may be easily removed by filtration. The hydrazinophosphine may then be recovered from the filtrate in good yield by evaporation of the solvent at room temperature under reduced pressure. 

University of Florida, Gainesville, Fla. t Hooker Chemical Corporation, Niagara Falls, N.Y. t Both reactants are commercially available. Diphenylphosphinous chloride was obtained from the Victor Chemical Division, Stauffer Chemical Company, Chicago Heights, 111. Unsj/m-dimethylhydrazine was obtained from the Eastman Kodak Company, Rochester, N.Y., but may be obtained from several sources. 

Tetranitrogen tetrasulfide is prepared by the method of Villena-Blanco and Jolly" and is recrystallized from toluene before use. Diphenylphosphinous chloride (Aldrich) is used as received. Acetonitrile is dried over phosphorus pentoxide and then calcium hydride, and distilled from CaH2 when needed. The reaction is carried out in an oven-dried one-necked 100-mL flask fitted with a side arm and under an atmosphere of dry nitrogen, which is also used for the work-up procedure. 

Kende has demonstrated that the mixed anhydride from carboxylic acids and diphenylphosphinic chloride would acylate Grignard reagents to afford ketones in moderate to good yield. Tertiary carbinols were not observed unless excess Grignard reagent was added. The intermediate anhydrides were generally isolated and made free of triethylamine hydrochloride before addition of the nucleophile. The reaction shown in equation (52) gave improved yields over the simple addition of methyllithium to the carboxylic acid. ... 

Commercial reagent grade diphenylphosphinyl chloride from Aldrich Chemical Company, Inc. was used as obtained. This compound can be prepared either by oxidation of diphenylphosphinous chloride with dimethyl sulfoxide or by the treatment of diphenylphosphinic acid with phosphorus pentachlorlde. ... 

Hydroxylamines usually react with acid chlorides to give mixtures of N-, O- and poly-acylated products. In contrast reaction of tris(trimethylsilyl)hydroxylamine (65) with aliphatic acid chlorides leads selectively under /V-monoacylation to the corresponding hydroxamic acids (66 equation 26). While di-phenylphosphinic chloride (68) is attacked by the oxygen of hydroxylamine to yield 0-(diphenylphos-phinyl)hydroxylamine (67 Scheme 13), A -(diphenylphosphinyl)hydroxylamine (69) can be obtained by treatment of diphenylphosphinic chloride with 0-trimethylsilylhydroxylamine followed by removal of the silyl blocking group (Scheme 13). 0-Acylation of arylhydroxylamines can be achieved with acyl cyanides. ... 

For the preparation of dppa, diphenylphosphinic acid (Aldrich) was transformed into diphenylphosphinic chloride by reaction with sulfinyl chloride3 (82% yield). The dppa (mp 164-166°) was obtained in 75% yield by reaction of the diphenylphosphinic chloride with concentrated ammonia, according to the method of Zhmurova et al.6... 

Uses of Phosphonic and Phosphinic Acid Derivatives -Analogues of Lawesson s reagent have been employed in the preparation of thiopeptides and the diphenylphosphinothioyl group protects tryptophane during peptide synthesis.Diphenylphosphinic chloride assists in the formation of 3-lactams from 249... 

A structurally related acid, 3-methoxycarbonyl-5-methylhexa-3,5-dienoic acid in dichloromethane solution with N-methylmorpholine and diphenylphosphinic chloride in the same solvent at -23°C was stirred for 0.5 hour and triethylamine added to the mixture which was then allowed to reach ambient temperature over approximately 1.5 hours. Methyl 3-hydroxy-5-methylbenzoate was obtained in 50% yield (ref.61) by a process having some similarity to Horner-Emmons methodology. 

Prepared by reaction of diphenylphosphinic chloride and pentafluorophenol with imidazole. 

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