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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A simple and efficient method for the synthesis of derivatives of arylphosphonic and phosphinic acids and phosphine oxides was developed. The method is based on palladium-catalyzed arylation of hydrophosphoryl compounds under conditions of phase transfer catalysis.The reactions of esters of phosphoric (phosphonic) acids and diphenytphosphinic acid with iodo-or bromoarenes readily occur at 70--80 ~ in the presence of 2 mol.% of a palladium catalyst, potassium carbonate, and benzyltriethylammonium chloride (BTEAC) without a solvent for liquid aryl halides or in acetonitrile in the case of solid aryl halides. Derivatives of the corresponding acids with tetracoordinated phosphorus and phosphine oxides were obtained in 65--100% yields, l,zThe palladium-catalyzed arylation of dialkyl phospites with iodo-and bromoarenes was accomplished using palladium(I0 acetate as the precursor of the catalyst, i.e., without a phosphine ligand. The use of Pd(OAe)2--2L (L = Ph3P, (2-furyl)3P) as the precursor of the catalyst markedly increases the rate of the reaction of dialkyl phosphites with aryl bromides but has no significant effect on the reaction with aryl iodides.Based on the palladium-catalyzed arylation of dimethyl phosphite with bromoarenes under conditions of phase transfer catalysis, we developed a versatile preparative procedure for the synthesis of arylphosphonic acids containing various substituents in the aromatic ring, which had been difficult to obtain previously) Potassium carbonate (9 mmol) was added with stirring to a hydrophosphoryl compound (9 mmol) placed in a Schlenk vessel pre-filled with argon. The mixture was stirred for 15 rain, and then BTEAC (0.9 mmot) and aryl halide (11 retool) were successively added (in the case of solid aryl halide, 0.5 mL of MeCN was also added). The reaction mixture was stirred for 5 rain, and a phosphine ligand (triphenylphosphine or tris(2-furyl)phosphine) (0.36 mmol) and palladiurn(I0 acetate (0.18 mmol) were added. The mixture was kept at 70--80 ~ for 6--10 h in the case of aryl iodides and for 20--22 h in the case of ary/bromides. After that, 3 mL of 2 M HC1 was added to the reaction mixture, and the resulting solution was filtered. The organic layer was separated, and the aqueous layer was extracted with ether (5x5 mL). The ethereal extracts were combined with the organic layer, the solvent was evaporated, and the residue was distilled in vacuo. The yields of phosphonates, phosphinates, and phosphine oxides were 65--100%. Physicochemical characteristics of the resulting compounds correspond completely to published values. 4

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Palladium-Catalyzed Arylation of O,O-Dialkyl Phosphites underPhase-Transfer Catalysis Conditions.-The palladium-catalyzed arylation of dialkyl phosphites (I), (IV), and (IX) under phase-transfer conditions is studied. The diethyl (I) and diisopropyl phosphites (IX) undergo cross-coupling with aryl halides (II) to give the corresponding arylphosphites (III) and (X), respectively. The iodides prove to be more reactive than the corresponding bromides. The same reaction is observed for dimethyl phosphite (IV), however, the so formed arylphosphites easily undergo acidic hydrolysis to afford the arylphosphonic acids (VI) and (VIII). -(KABACHNIK, M. M.; SOLNTSEVA, M. D.; IZMER, V. V.; NOVIKOVA, Z. S.; BELETSKAYA, I. P.; Zh.