107-49-3

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Boranephosphonate diesters react with heteroaromatic and certain tertiary amines in the presence of an oxidant (I2) to afford the boron-modified phosphodiester analogues containing a P-B-N structural motif. Our multinuclear 31P and 11B NMR spectroscopy studies lend support for a two-step mechanism involving generation of a λ3-boranephosphonate intermediate that immediately coordinates an amine in the solvent cage, leading to B-pyridinium or B-ammonium boranephosphonate betaine derivatives. We found that the type of the solvent used (e.g., dichloromethane vs acetonitrile) significantly affected the course of the reaction, resulting in either formation of boron-modified derivatives or loss of the boron group with a subsequent oxidation of the phosphorus atom. In aprotic, electron-donating, polar solvents., e.g., acetonitrile (ACN) and tetrahydrofuran (THF), a λ3-boranephosphonate intermediate can also coordinate solvent molecules forming P-B-ACN or P-B-THF complexes that may influence the type of the products formed.

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Activated phosphoryl compounds react with phosphoryl anions to give anhydrides without the intervention of dioxadiphosphetane intermediates; the mechanism has been probed using oxygen isotopes and high field 31P n.m.r. spectroscopy.

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A n-Bu4NI/t-BuOOH catalysis system has been developed to promote oxidative dehydrogenative coupling of H-phosphonates to form pyrophosphate tetraesters. This novel iodide (I) ion-catalyzed reaction provides easy access to pyrophosphate derivatives in the absence of a metal and solvent. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. Taylor and Francis Group, LLC.

It has been established that the process of splitting of the P-P bonds of the white phosphorus molecules is initiated by cathode-generated nucleophiles (HO-, RO-), while functionalization of the P-H bond formed in phosphoric oligomers occurs under the action only of alcohol.The primary product after splitting of all the P-P bonds in phosphoric oligomers is dialkylphosphite (in alcohol-water media), or trialkylphosphite (in absolute alcohol), in the course of electrolysis being transformed into trialkylphosphate.Formation of esters of pyrophosphoric acid with reduced protogenic character of the medium was examined.It is proposed that under these conditions nucleophilic reagents of the type (>P)c-O- form and participate in splitting of the P-P bonds. Keywords: phosphoric acid derivatives, white phosphorus, electrosynthesis, alcohol-water solution.

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In this contribution, a metal- and base-free protocol has been developed for the synthesis of phosphorochalcogenoates (Se and Te) by using DMSO as solvent at 50 °C. A variety of phosphorochalcogenoates were prepared from diorganyl dichalcogenides and H-phosphonates, leading to the formation of a Chal-P(O) bond, in a rapid procedure with good to excellent yields. A full structural elucidation of products was accessed by 1D and 2D NMR, IR, CGMS, and HRMS analyses, and a stability evaluation of the phosphorochalcogenoates was performed for an effective operational description of this simple and feasible method. Typical 77Se{1H} (δSe = 866.0 ppm), 125Te{1H} (δTe = 422.0 ppm) and 31P{1H} (δP = ?1.0, ?13.0 and ?15.0 ppm) NMR chemical shifts were imperative to confirm the byproducts, in which this stability study was also important to select some products for pharmacological screening. The phosphorochalcogenoates were screened in vitro and ex vivo tests for the antioxidant potential and free radical scavenging activity, as well as to investigation toxicity in mice through of the plasma levels of markers of renal and hepatic damage. The pharmacological screening of phosphorochalcogenoates indicated that compounds have antioxidant propriety in different assays and not changes plasma levels of markers of renal and hepatic damage, with excision of 3g compound that increased plasma creatinine levels and decreased plasma urea levels when compared to control group in the blood mice. Thus, these compounds can be promising synthetic antioxidants that provide protection against oxidative diseases.

We report a diaryldiselenide catalyst for cross-dehydrogenative nucleophilic functionalization of hydrophosphoryl compounds. The proposed organocatalytic cycle closely resembles the mechanism of the Atherton-Todd reaction, with the catalyst serving as a recyclable analogue of the halogenating agent employed in the named reaction. Phosphorus and selenium NMR studies reveal the existence of a P-Se bond intermediate, and structural analyses indicate a stereospecific reaction.

A systematic study on the iodine-mediated phosphoramidation reaction of amines and trialkyl phosphites was conducted, which not only disclosed the factors affecting the reaction but also revealed that it could proceed smoothly in CH2Cl2 at room temperature in open air. Using this method, various phosphoramidates with different aliphatic amines and aromatic amines were synthesized in good to excellent yields. Our present investigation shows that this underused method is actually a mild, practical and general way to synthesize phosphoramidates and will have wide applications.

The copper-catalysed oxidative coupling of amines and H-phosphonates to produce phosphoramidates has been achieved using CuI as the catalyst and O 2 (present in air) as the sole oxidant.

Copper-catalyzed aerobic oxidative trifluoromethylation of readily accessible H-phosphonates was demonstrated for the first time. This method not only provides an alternative method for the facile synthesis of a series of biologically important CFphosphonates, but also demonstrates the first example of the efficient construction of a P-CFbond via transition-metal catalysis.

(Chemical Equation Presented) Different copper complexes selectively catalyze the aerobic oxidative coupling of H-phosphonates to afford either hypophosphates and pyrophosphates in high yields with high selectivity (see scheme; tmeda = N, N, N', N'-tetramethylethylenediamine).

A novel reaction between sodium salt of phenylphosphinic acid PhP(O)(OH)H (1) and various phosphorus electrophiles, R2P(O)C1 (2; R = alkyl, aryl, alkoxy or aryloxy) has been described. The presented reaction showed a high selectivity (yield up to 96%) in the products of the symmetric phosphorus anhydrides, R2P(O)-O-(O)PR2(4), which preferentially come from the starting phosphorus electrophiles (2). The results demonstrate that the phosphorus-phosphorus mixed anhydrides, RPH(O)-O-(O)PR2(3) are unstable under basic condition and possibly decomposed with expulsion of a phosphinylidene (Ph-P=O) fragment (6).

Simple syntheses of phosphoric (4) and carboxylic (6) acid anhydrides have been elaborated by means of solid potassium carbonate in phase-transfer catalytic acylation. Behavior of various acid chlorides, phosphoric (1), sulfonic (2), and carboxylic (8), have also been studied toward potassium carbonate in the presence of lipophilic quaternary ammonium salt.

Alkali metal salts of diethyl phosphites act as nucleophiles or electron donors in reactions with diethyl phosphorochloridate. Evidence is provided that formation of the direct P(IV)-P(IV) bond proceeds via a single electron transfer process (SET) from phosphite anion to phosphorochloridate.

The reaction of iodosylbenzene with > P(O)H type of acids (dialkyl phosphites, secondary phosphine oxides) was studied. The acids of >P(O)H type add to iodosylbenzene to yield intermediate 6 which in the aprotic solvents yields oxidation products, it means >P(O)OH acids and/or anhydride of >P(O)OP(O) P(O)OR ester is the major product.

The 31P nuclear magnetic resonance (NMR) evidence for the formation of diorganyl phosphoropyridinium intermediates was reinvestigated. It was found that equilibria of these reactions were heavily shifted to the left. The concentrations of the putative diorganyl phosphoropyridinium chlorides/bromides were usually below the detection level of this spectroscopic method. The results showed that when diphenyl iodophosphate was subjected to reaction with pyridine, the formation of a diorganyl phosphoropyridinium intermediate was observed.

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Electrochemical oxidation of sodium dialkyl phosphites with alkyl radicals of normal structure leads to formation of tetraalkyl pyrophosphites as the main products, while electrochemical oxidation of litium dialkyl phosphites and sodium salts with branched alkyl radicals yields tetraalkyl hypophosphates. The reaction of metal dialkyl phosphites with halogens leads to analogous results.

α-Halogenomethyl alkyl(aryl) sulphoxides have been found to undergo nucleophilic attack by dialkyl phosphite anions at the α-carbon atom and/or at halogen.

Treatment of N-trimethylsilyllactams with phosphoryl chlorides results in mixtures of products, whose formation can be explained by competition between N- and O-phosphorylation. - Key words: N-trimethylsilyllactams, dual reactivity; N-phosphoryllactams, synthesis.

Esterification of phosphates with various halides, including acid chlorides, phosphoryl trichloride and chloride, was achieved in 57-99percent isolated yield using silver(I) oxide.The reaction was successfully applied to the preparation of phosphate triesters sensitive to acids and bases. cAMP benzyl esters were also prepared by this method.

Dimethylthiocarbamoyl chloride reacts with pyridine 1-oxide with the formation of 1-(dimethylthiocarbamoyloxy)pyridinium chloride.The reaction of dialkyl phosphorochloridates with pyridine 1-oxide lead to the formation of 1-(dialkoxyphosphinyloxy)pyridinium chlorides together with tetraalkyl pyrophosphates.

5-Alkyl-4,5-dihydro-1,2,4-triazin-6(1H)-ones are phosphorylated by phosphorochloridic and phosphorochloridothioic esters on the N4 atom of the triazine ring and in some cases also on the carbonyl oxygen.The formation of diphosphorylated triazines is explained by the presence of the tautomeric hydroxy form of the triazine, which is realized under the conditions of the reaction.

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Mixed trialkyl phosphonates were synthesized by oxidative phosphorylation of alcohols with dialkyl phosphonates and oxygen in the presence of copper(II) chloride in fairly good yields.

A novel efficient synthesis of sym-monoselenopyrophosphates 3 based on the reaction of diphosphoryl diselenides 1 with dialkyltrimethylsilyl phosphites 2 is described.

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Arylphosphonates 5 and 6 can be prepared in good yields in a one-step synthesis starting from arenes with tri- or diethylphosphites and cerium ammonium nitrate (CAN) as oxidant.The seletivity of the oxidative phosphonylation is relatively low; the reactive species is a phosphite radical cation.

Oxidation of phosphonate mono- and di-esters with various oxidizing agents including diaryl disulphides, hexacloroacetone, and iodine, has been investigated under various reaction conditions.The most efficient oxidation procedure consists of treatment of phosphonate esters with iodine in pyridine-water.When the phosphonate esters were presilylated by treatment with trimethylsilyl chloride, the subsequent oxidation with aqueous iodine was faster. (31)P N.m.r. spectroscopic studies have enabled us to propose the most likely pathway for the majority of the oxidations.

Monocyclic chlorophosphoranes 1 and 2 have been used as models for investigations of nucleophilic displacement reactions at the pentacoordinate phosphorus atom.The chlorine ligands of 1 and 2 can be exchanged by nucleophiles under very mild conditions.Synthesis of the pentacoordinate phosphorus systems 4 and 5 via the reactions of 1 and 2 with a variety of nucleophiles is demonstrated.Special attention is paid to the reactions of chlorophosphoranes with such nucleophiles as organic phosphorus acids and thiocyanates.

A kinetic study of alcoholysis and aminolysis of 2-chloro-2-oxo-1,3,2-dioxaphospholane, 1, shows a rate levelling effect of the nucleophile, where the stereochemistry is retention at phosphorus.On the other hand, the substitutions with inversion of the 2-chloro-2-oxo-1,3,2-dioxaphosphorinane 2, or the diethylchlorophosphate, 3, show a marked influence of the nucleophile upon the reactivity.Furthermore, the large rate increase which has been observed for the hydrolysis of the five-membered ring phosphorus esters compared to phosphates (an oxygen always displaces an oxygen) is not reproduced when the leaving group is different of the nucleophile.We suggest that the mechanistic implications, established in the case of phosphate esters hydrolysis cannot be directly extended to the general case of SN2(P).The mechanism of nucleophilic substitution of P(4) species is better interpreted in terms of HOMO-LUMO interactions between the nucleophile and the substrate, a process now well established in silicon chemistry.

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New applications of methods leading to anhydrides RR'P(O)OSO2R'' (1) are described: a) Reaction of acids RR'P(O)OH (2) with sulfonic imidazolides. b) Reaction of phosphorus imidazolides 4 with sulfonic acids and sulfonic anhydrides.New methods of synthesis of anhydrides 1 have been developed. c) Reaction of phosphorus acid silyl esters RR'P(O)OSiMe3 (9) with methanesulfonic and trifluoromethanesulfonic anhydrides. d) Reaction of bis(trimethylsilyl) tert-butylphosphonate (10) with methanesulfonic acid leading to tBuP(O)(OSO2Me)2 (11). e) Reaction of stannyl phosphate (EtO)2P(O)OSnMe3 (15) with methanesulfonic anhydride. f) Reaction of phosphorus acid silyl esters 9 with trimethylsilyl trifluoromethanesulfonate.All methods result in high yields and can be adapted to a variety of anhydrides 1 derived from phosphoric, phosphonic, and phosphinic acids on the one hand and methanesulfonic, trifluoromethanesulfonic acids and sulfuric monoimidazolide on the other.Phosphonium intermediates have been demonstrated by low temperature FT 31P NMR spectroscopy for reaction b) and c).The anhydrides 1 are readily converted into imidazolides 4 by the reaction with N-(trimethylsilyl)imidazole which proceeds via two distinct phosphonium intermediates.With neutral and weakly basic nucleophiles, the anhydrides 1 behave as phosphorylating agents.

N,N,N',N'-Tetramethylchloroformamidinium chloride reacted smoothly with a variety of carboxylic and phosphoric acids in the presence of a tertiary amine to give the corresponding acid anhydrides in high yields.

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Various alkyl 4-[o-(substituted methyleneamino)phenyl]3-thioallophanates are useful as fungicides and mite ovicides. The compounds are prepared by reacting alkyl 4-(o-aminophenyl)-3-thioallophanates with aldehydes or trialkyl orthoformates. Some of the compounds are prepared by further reacting the reaction product of an alkyl 4-(o-aminophenyl)-3-thioallophanate and a trialkyl orthoformate with a primary or secondary amine. Exemplary species are methyl 4-[o-(o-fluorobenzylideneamino)phenyl]-3-thioallophanate, methyl 4-[o-(4-methylbenzylideneamino)phenyl]-3-thioallophanate and methyl 4-[o-(2-furfurylideneamino)phenyl]-3-thioallophanate.

Various alkyl 4-[o-(substituted methyleneamino)phenyl] 3-thioallophanates are useful as fungicides and mite ovicides. The compounds are prepared by reacting alkyl 4-(o-aminophenyl)-3-thioallophanates with aldehydes or trialkyl orthoformates. Some of the compounds are prepared by further reacting the reaction product of an alkyl 4-(o-aminophenyl)-3-thioallophanate and a trialkyl orthoformate with a primary or secondary amine. Exemplary species are methyl 4-[o-(o-fluorobenzylideneamino)phenyl]-3-thioallophanate, methyl 4-[o-(4-methylbenzylideneamino)phenyl]-3-thioallophanate and methyl 4-[o-(2-furfurylideneamino)phenyl]-3-thioallophanate.

Propynyl benzyl ethers having juvenile hormone-like activity which are 4-halogen, lower alkyl, lower alkoxy or propynyloxy substituted or 3,4-lower alkylenedioxy substituted and which can also be 3,5- and/or α-substituted, and insecticide compositions that include at least one propynyl benzyl ether and that can also include a conventional insect-poison.

Formamidine compounds of the formula EQU1 or WHEREIN R1 represents a substituted or unsubstituted phenyl radical, R2 represents hydroogen, alkyl, alkenyl or alkinyl and R3 represents acyl their manufacture and their use in pest control.

Various alkyl 4-[o-(substituted methyleneamino)phenyl] 3-thioallophanates are useful as fungicides and mite ovicides. The compounds are prepared by reacting alkyl 4-(o-aminophenyl)-3-thioallophanates with aldehydes or trialkyl orthoformates. Some of the compounds are prepared by further reacting the reaction product of an alkyl 4-(o-aminophenyl)-3-thioallophanate and a trialkyl orthoformate with a primary or secondary amine. Exemplary species are methyl 4-[o-(o-fluorobenzylidine-amino)phenyl]-3-thioallophanate, methyl 4-[o-(4-methylbenzyl-ideneamino)phenyl]-3-thioallophanate and methyl 4-[o-(2-furfuryl-ideneamino)phenyl]-3-thioallophanate.