- First synthesis of etidronate partial amides starting from PCl3.
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Methods for the preparation of mixed tetra-amide esters 1 and 2, the partial amide ester 3, and tri- and P,P-diamides 4 and 5 from monophosphorus spieces 12, 8 and 9, respectively, were developed. Compounds 8 and 9 were obtained from phosphorus trichloride via MeOPCl2, which was treated with 2 eq. and 4 eq. of piperidine, followed by water or acetyl chloride, respectively. Tetrasubstituted amide bisphosphonates 1 and 2 were selectively dealkylated with lithium or silyl halide to achieve target compounds 3-5. Piperidine was found to be a good desilylation reagent. Quantum mechanical calculations illustrate why derivative 2 was produced in low yield. The usefulness of compounds 1, 3 and 4 as prodrugs of etidronate was determined in aqueous buffer and human serum.
- Turhanen, Petri A,Niemi, Riku,Peraekylae, Mikael,Jaervinen, Tomi,Vepsaelaeinen, Jouko J
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- Kinetics and mechanism of the pudovik reaction in the azomethine series: II.1 Hydrolysis and catalysis in the reaction of dialkyl phosphites with benzalaniline
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A 31P NMR study show that diisopropyl phosphite and benzalaniline do not react with each other as individual components. Adduct formation is made possible by partial hydrolysis of the dialkyl phosphite.
- Sobanov,Zolotukhin,Galkin,Mostovaya,Cherkasov,Pudovik
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- Novel routes to aminophosphonic acids: Interaction of dimethyl H-phosphonate with hydroxyalkyl carbamates
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It was found that the reaction of dimethyl H-phosphonate (1) with 2-hydroxyalkyl-N-2′-hydroxyalkyl carbamates at 135°C includes several chemical reaction steps: (i) chemical transforma-tions of 1-methyl-2- hydroxyethyl-N-2′-hydroxyethyl carbamate (2) and 2-methyl-2-hydroxyethyl- N-2′-hydroxyethyl carbamate (3); (ii) transesterification of dimethyl H-phosphonate with 2 and 3, and with secondary hydroxyl-containing compounds that are formed during the course of the chemical transformation of 2-hydroxyalkyl-N-2′-hydroxyalkyl carbamates; (iii) hydrolysis of 1 and dialkyl H-phosphonates, formed via transesterification of 1 with secondary hydroxyl-containing compounds. The interaction was studied by means of 1H, 13C, 31P NMR, and FAB mass spectroscopy.
- Troev,Koseva,Haegele
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- The formation of dimethyl amino(pyrene-1-yl)methylphosphonates in the Kabachnik-Fields reaction with dibenzyl phosphite, pyrene-1-carboxaldehyde and a non-aromatic amine in methanol
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The Kabachnik-Fields reaction of pyrene-1-carboxaldehyde with dibenzyl phosphite and aliphatic amines in methanol led to the formation of dimethyl amino(pyren-1-yl)methyl-phosphonates, in some cases accompanied by dimethyl hydroxy(pyren-1-yl)methyl-phosphonate. These results are exclusive for the above compounds, in all other studied cases (aromatic aldehydes, aromatic amines) the mixtures of several aminophosphonates were obtained.
- Lewkowski, Jaros?aw,Rodriguez Moya, Maria
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p. 713 - 718
(2017/06/05)
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- Protonation and alkylation of organophosphorus compounds with trifluoromethanesulfonic acid derivatives
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Protonation (alkylation) of triphenylphosphine, triethylphosphite, triphenylphosphine oxide, triethylphosphate, hexamethylphosporamide, and dimethylphosphite with trifluoromethanesulfonic acid, its bisimide, and methyl ester was studied and the corresponding 1H, 13C, 19F, 31P NMR spectra were analyzed.
- Tolstikova,Bel'Skikh,Shainyan
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experimental part
p. 474 - 480
(2011/06/23)
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- PROCESS FOR THE MANUFACTURE OF DIALKYLPHOSPHITES
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A process for the manufacture of dialkyl phosphites is disclosed. In detail, dialkyl phosphites are prepared starting from P4O6, or partially hydrated species thereof cumulatively P-O, by reacting specific molar ratios of alcohol and P-O, containing from 1 to 6 P-O-P bonds in the molecule, in the presence of trialkylphospite (TAP) to thus yield high purity and high yield of dialkyl phosphites. The P-O reactant is preferably represented by liquid P4O6.
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Page/Page column 8
(2010/12/26)
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- Reconsideration of the base-free batch-wise esterification of phosphorus trichloride with alcohols
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Batch-wise esterification of phosphorus trichloride with different alcohols in the absence of base and cleavage of the reaction products by the HCl released in course of the reaction were reinvestigated. The role of the kind of alcohol, mixing order of reagents, temperature, time of reaction, and excursion of gaseous HCl in the proportional composition of the reaction products were studied. Considering the mechanism of esterification and cleavage of the products, the optimized conditions to retain the cleavage process and high-yield production of dialkyl hydrogen phosphonates were determined.
- Fakhraian,Mirzaei
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p. 401 - 404
(2013/09/05)
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- A novel and convenient method for synthesizing unsymmetrical - Benzyloxycarbonyl-protected 1-amino-1-arylalkylphosphonate mixed diesters
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Unsymmetrical N-benzyloxycarbonyl-protected 1-amino-1-arylalkylphosphonate mixed diesters were synthesized using a one-pot reaction involving benzyl carbamate, aromatic aldehydes and alkoxydichlorophosphine, followed by treatment with alcohols in the presence of triethylamine. The reactions were followed by 31P NMR and a mechanism is proposed.
- Xu,Fu
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p. 1223 - 1226
(2007/10/03)
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- The influence of ultrasound on the addition of phosphites to thiophenecarbaldehydes
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Diethyl phosphites add to the carbonyl double bond of thiophenecarbaldehydes.This is solely an ionic process in the presence of a base, and ultrasound has no influence on it.However in the absence of base, a free radical mechanism occurs which is promoted by ultrasound.It is shown here that when the ionic process is catalyzed by triethylamine or potassium fluoride, it is faster than the free radical process in all conditions. - Key words: phosphite / ultrasound / thiophenecarbaldehyde
- Oussaid, Boualem,Diallo, Ousmane,Soufiaoui, Mohammed,Garrigues, Bernard
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p. 461 - 466
(2007/10/02)
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- ALKYLATING PROPERTIES OF DIALKYL PHOSPHITES
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When the mixture of amines and dialkyl phosphites is used in the reaction, as for example in the Kabachnik-Fields reaction, all possible N-alkylated products are formed.N-ethylation by diethyl phosphite is much slower than N-methylation by dimethyl phosphite and the latter can be easily formed via transesterification when the methanol is present in the mixture.Key words: Amine alkylation, dialkyl phosphites, Kabachnik-Fields synthesis.
- Gancarz, Roman
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p. 193 - 200
(2007/10/02)
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- PMR STUDY OF THE ACIDOLYSIS OF DIMETHYL HYDROGEN PHOSPHITE
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The acidolysis of dimethyl hydrogen phosphite was studied by means of PMR spectroscopy.The acidolysis was found to go in two stages.In its character it belongs to the consecutive-reactions type.
- Kaslina, N. A.,Krinitskaya, L. V.,Kessenikh, A. V.,Balashova, T. V.,Reshetnikov, Yu. P.
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p. 1252 - 1254
(2007/10/02)
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- PHOSPHORUS-CONTAINING HMG-COA REDUCTASE INHIBITORS, NEW INTERMEDIATES AND METHOD
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Compounds which are useful as inhibitors of cholesterol biosynthesis and thus as hypocholesteroleumic agents are provided which have the structure STR1 wherein R is OH, or salts thereof or lower alkoxy; R. sup.x is H or alkyl;X is--CH 2--,--
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- Sulphonic Acid-induced Fragmentation of Dialkyl Acylphosphonates, Formation of Alkyl Carboxylates and Alkyl Sulphonates
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Heating of dialkyl acylphosphonates with sulphonic acids under anhydrous conditions leads to the formation of alkyl sulphonates and alkyl carboxylates. 31P N.m.r. spectroscopy revealed that the reaction of equimolar amounts of dimethyl benzoylphosphonate (1) and toluene-p-sulphonic acid at room temperature gives dimethyl phosphonate (6) in 50percent yield.It is proposed that the by-product of this reaction, benzoic toluene-p-sulphonic anhydride (8), reacts with the excess of toluene-p-sulphonic acid, to yield toluene-p-sulphonic anhydride (9) and benzoic acid.Heating of these two compounds with dimethyl phosphonate was shown to yield methyl toluene-p-sulphonate and methyl benzoate, respectively.A postulated by-product of these reactions is phosphenous acid (HPO2).Quantum mechanical calculations by the MNDO/H method carried out on dimethyl benzoylphosphonate and its protonation products show that the preferred site of protonation of dimethyl benzoylphosphonate is the P=O oxygen, and that protonation at this site is followed by C-P bond breaking, with zero energy of activation, leading to dimethyl phosphite and benzoylium cation.
- Breuer, Eli,Karaman, Rafik,Goldblum, Amiram,Leader, Haim
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p. 2029 - 2034
(2007/10/02)
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- ON THE SIDE REACTIONS ACCOMPANYING THE TRANS-ESTERIFICATION OF THE ACID DIESTERS OF PHOSPHOROUS ACID
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The side reaction accompanying the trans-esterification of the acid diesters of phosphorous acid is studied, leading to the formation of R-O-R type ethers, where R is the aliphatic group of the acid ester.The products of the side reaction are identified by 1H and 13C-NMR spectroscopy.It is shown that the R-O-R ether is formed as a result of the pyrolysis of dimethyl phosphite.
- Troev, K.,Simeonov, M.
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p. 363 - 368
(2007/10/02)
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