Umsetzungen von 1-Aminoalkan-1,1-diphosphonsäuren mit salpetriger Säure

Reactions of 1-Aminoalkane-1,1-diphosphonic Acids with Nitrous Acid Compounds of the structure RC(NH₂)(PO₃H₂)₂ 1 give products RC(OH)(PO₃H₂)₂ 2 in high yields by the reaction with nitrous acid. In contrast, when R = Aryl the reaction of 1 often gives in concentrated hydrochloric acid RCCl(PO₃H₂)₂ 3 . Exceptions to the above reaction are described.     

1-Alkoxy(aryloxy)alkylidene-1,1-diphosphonic acids

Conclusions Alkyl carboxylates react with mixtures of H₃PO₃ and PCl₃ and with P₄O₆ in the presence of BF₃ to give 1-alkoxyalkylidene-1,1-diphosphonic acids. Formates are much more reactive than other esters in this reaction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 624–630, February, 1987.     

Peroxophosphorsäuren

Reaction between P₄O₁₀ and H₂O₂ yields the hitherto unknown Diperoxo monophosphoric acid, H₃PO₆ (VI). The new compound is also the product of the reaction between P₂O₃Cl₄ or OPCl₂(OH) with H₂O₂. Solvolysis of P₂O₃F₄ with H₂O₂ leads to the formation of Difluoro peroxo monophosphoric acid, HPO₃F₂ (XI), which has not been known as yet. Monofluoro peroxo monophosphoric acid, H₂PO₄F (IV), is formed in the reaction between OPCl₂F with H₂O₂ in good yield. Properties, especially NMR data of the new compounds and other peroxo acids of phosphorus are described.     

Enzyme-catalysed Transformations of Compounds Containing the –CH2-AsO3H2 Group

Enzymes that act on substrates R–O–PO₃H₂ often work on substrate analogues R–O–AsO₃H₂; such substrates are unstable, since esters of H₃AsO₄ hydrolyse easily. They also form easily, so that an enzyme that acts on R–O–PO₃H₂ often acts on a mixture of R–OH and arsenate via an ester that forms at the active site. Similarly coenzyme analogues may be formed; for example, a stable and active aspartate aminotransferase forms from the apoenzyme with free pyridoxal and arsenate. Enzymes that convert R–O–PO₃H₂ into a diester often act on R–CH₂–AsO₃H₂, a stable substrate analogue; then the product is unstable and hydrolyses to re-form the analogue, giving a futile cycle. For example, RNA polymerase acquires exonuclease activity in the presence of H₂O₃P–CH₂–AsO₃H₂; adenylate kinase acquires ATPase activity in the presence of the arsonomethyl analogue of AMP. A recent observation is that HO–CH₂–CHOH–CH₂–CH₂–AsO₃H₂ is a good substrate for glycerol-3-phosphate dehydrogenase. The product is unstable and eliminates arsenite, sharing this ability with other 3-oxoalkylarsonates. Thus this enzyme–catalysed oxidation is a lethal synthesis, in view of the toxicity of arsenite. Another unusual biochemical reaction of an arsonic acid is seen in the ability of a bacterium to use arsonoacetate as its sole source of carbon and energy. In contrast with the elimination of arsenite by 3-oxoalylarsonic acids, 3-oxoalkylphosphonic acids, R–CO–CH₂–CH₂–PO₃H₂, are stable. 2-Oxoalkylphosphonic acids, R–CO–CH₂–PO₃H₂, however, are moderately unstable to hydrolysis, yielding phosphate and R–CO–CH₃. 2-Oxoalkylarsonic acids, R–CO–CH₂–AsO₃H₂, decompose in the same way, but much more readily, yielding arsenate. © 1997 by John Wiley & Sons, Ltd.     

Die Reaktionen von Benzoylierungsmitteln mit Phosphoriger Säure

Reactions of Benzoylating Agents with Phosphorous Acid H₃PO₃ reacts with (C₆H₅CO)₂O to yield C₆H₅C(OH)(PO₃H₂)₂ 1 . In contrast, the reaction with C₆H₅COCl proceeds with the formation of C₆H₅CCl(PO₃H₂)₂ 2 and p-ClC₆H₄CH(PO₃H₂)₂ 3 . The best yields of 2 and 3 are obtained, if the reaction are carried out under pressure. 2 is rapidly hydrolysed in alkaline solution at elevated temperatures to 1 .     

Unexpected Rearrangement in the Reaction of 7‐Mercapto‐4‐methylcoumarin with 1‐Mono‐ and 1,1‐Dimethyl Propargyl Alcohols

The reaction of 7‐mercapto‐4‐methylcoumarin (4) with 1‐mono‐ and 1,1‐dimethyl propargyl alcohols in H₃PO₄ afforded the corresponding β‐(7‐coumarinthio)ketones with a rearrangement of the carbon chain of propargyl. A possible mechanism of this rearrangement was proposed.     

Novel nucleophilic C?C bond‐forming tele‐reaction of imidazole ring

Reaction of 2‐(1‐chloro‐2,2‐dimethylpropyl)‐1‐methyl‐1H‐irnidazoles with diethyl methylmalonate in the presence of NaH gave a normal S_N product, 2‐[(1,1‐diethoxycarbonylethyl)‐2,2‐dimethylpropyl]‐1‐methyl‐1H‐imidazole (2a) , and two tele‐reaction products, 5‐(1,1‐diethoxycarbonylethyl)‐1‐methyl‐2‐(2,2‐dimethylpropyl)‐1H‐imidazole (3a) and trans‐4,5‐di‐(1,1‐diethoxycarbonylethyl)‐4,5‐dihydro‐1‐methyl‐2‐(2,2‐dimethylpropyl)‐1H‐imidazole (4a) in 5, 17 and 70% yields, respectively. The scope and mechanism of this reaction are discussed.     

Copper(II) complexation by (pyridinyl)aminomethane-1,1-diphosphonic acid derivatives; spectroscopic and potentiometric studies

The complex formation between copper(II) and (pyridinyl)aminomethane-1,1-diphosphonic acid derivatives was studied by means of pH-potentiometry, spectroscopic methods (UV-Vis, EPR) and mass spectrometry (MS). The bisphosphonate ligands form polynuclear Cu₃H_xL₃ (x = 4 ,3, 2, 1, 0, −1) species besides the mononuclear 1:1 and 1:2 metal-to-ligand molar ratio complexes. Two phosphonate groups are basic binding sites for the metal ion. It is suggested that in the polynuclear complexes the ligands adopt chelating and bridging modes via the four oxygen atoms of the two phosphonate groups.     

Synthesis and Properties of Lead(II) 1-Hydroxyethane-1,1-diphosphonate(2-) Monohydrate

Conditions for isolation of a 1-hydroxyethane-1,1-diphosphonic acid (H₄L) complex of the composition PbH₂L·H₂O from aqueous solutions of various composition are studied. The X-ray analysis of the resulting polycrystalline sample showed that it is single-phase. The IR spectrum is presented, and the solubility and thermal transformations of the sample are studied.     

Kinetics and mechanism of the reduction of diaquotetrakis (2,2′-bipyridine)-µ-oxodiruthenium(III) ion by hypophosphorous acid in acidic medium

The kinetics and mechanism of the reduction of diaquotetrakis(2,2′-bipyridine)-µ-oxodiruthenium(III), [(H₂O)₂(bipy)₄Ru₂O]⁴⁺, by H₃PO₂ has been studied in aqueous acid at ionic strength = 0.5 mol dm^?3 (NaClO₄), [H⁺] = 5.0 × 10^?2 mol dm^?3 and temperature = 31 ± 1 °C. Measurement of the stoichiometry showed that 1 mole of [(H₂O)₂(bipy)₄Ru₂O]⁴⁺ was reduced by 1 mole of H₃PO₂. The reaction was found to be first order with respect to both [(H₂O)₂(bipy)₄Ru₂O⁴⁺] and [H₃PO₂], hence second order overall. Variations in the ionic strength and dielectric constant of the reaction medium had no effect on the rate. Also, addition of various ions to the reaction medium did not significantly alter the rate. Free radicals were identified during the course of the reaction by a polymerisation test. Spectroscopic information and Michaelis–Menten plots suggested the absence of an intermediate complex prior to electron transfer. [(H₂O)₂(bipy)₂Ru]²⁺, the reduction product of [(H₂O)₂(bipy)₄Ru₂O]⁴⁺, plus H₃PO₃, the oxidation product of H₃PO₂, were identified in the product solutions. It is suggested that the reaction proceeds through the outer sphere pathway. A mechanism for the reaction is proposed.     

Synthese und Kristallstruktur der Übergangsmetalltrimetaphosphimate Zn3[(PO2NH)3]2 · 14 H2O und Co3[(PO2NH)3]2 · 14 H2O

Synthesis and Crystal Structure of the Transition Metal Trimetaphosphimates Zn₃[(PO₂NH)₃]₂ · 14 H₂O and Co₃[(PO₂NH)₃]₂ · 14 H₂O The transition metal trimetaphosphimates Zn₃[(PO₂NH)₃]₂ · 14 H₂O and Co₃[(PO₂NH)₃]₂ · 14 H₂O were obtained by the reaction of an aqueous solution of Na₃(PO₂NH)₃ · 4 H₂O with the respective metal nitrate or halide (molar ratio 1 : 4). The structure of Zn₃[(PO₂NH)₃]₂ · 14 H₂O was solved by single crystal X‐ray methods. The structure of isotypic Co₃[(PO₂NH)₃]₂ · 14 H₂O was refined from X‐ray powder diffraction data using the Rietveld method (Zn₃[(PO₂NH)₃]₂ · 14 H₂O ( 1 ): P 1, a = 743.7(2), b = 955.9(2), c = 980.1(2) pm, α = 102.70(3), β = 90.46(3), and γ = 100.12(3)°, Z = 1; Co₃[(PO₂NH)₃]₂ · 14 H₂O ( 2 ): P 1, a = 746.05(1), b = 957.06(2), c = 988.51(2) pm, α = 102.162(1), β = 90.044(1), and γ = 99.258(1)°, Z = 1). In 1 and 2 the P₃N₃ rings of the trimetaphosphimate ions attain a conformation which can be described as a combination of an ideal boat and an ideal twist conformation. The trimetaphosphimate ions act as bridging ligands. Thus chains of alternating M²⁺ and (PO₂NH)₃^3– ions are formed which are interconnected by additional M²⁺ ions forming electro‐neutral double chains. In the solid these double chains are connected by hydrogen bonds.     

Preparation of water-soluble iron and manganese chelates with oxyethylidenediphosphonic acid

The following water-soluble iron(III) and manganese(II) chelate complexes were obtained via the reaction of 1-hydroxyethylidene-1,1-diphosphonic acid (H₄L) with ferric hydroxide or basic manganese carbonate: Fe₂(H₂L)₃·4H₂O, Fe(H₃L)₃·4H₂O, MnH₂L·2H₂O, and Mn(H₃L)₂·4H₂O. The complexes solubility was of 33.0, 1.40, 0.1, and 0.4 g in 100 mL of water, respectively. The amorphous Fe₂(H₂L)₃·4H₂O underwent structural changes upon storage, its solubility decreasing. The prepared compounds are recommended for use as micro-fertilizers for drip irrigation of crops.     

Interaction of K2PdCl4 with aminoalkyldiphosphonic acids

Complexing of K₂PdCl₄ with 3-amino-1-hydroxypropylidene-1,1-diphosphonic acid (AHPDP) and 1-aminoethylidene-1,1-diphosphonic acid (AEDP) was studied by pH titration, spectrophotometry, and ³¹P NMR spectroscopy using metal to ligand mole ratios of 1: 1 and 1: 2. In equimolar complexes, AHPDP is coordinated to palladium(II) via two phosphonic oxygen atoms, whereas AEDP is coordinated via the amino nitrogen atom and a phosphonic oxygen atom. In the bisligand palladium(II) complex with AEDP, both ligand molecules are coordinated in a bidentate mode by the amino nitrogen atom and a phosphonic oxygen atom.     

Herstellung von 1-Aminoalkan-1,1-diphosphonsäuren

1-Aminoalkane-1,1-diphosphonic acids 1 , 2 or 3 are formed in the reaction of carboxylic acid amide dihalides or carboxylic acid amide hydrohalogenides with phosphorous acid. Phosphorus trihalides plus water may be used in lieu of phosphorous acid in the reaction with carboxylic acid amides. With formamide either aminomethanediphosphonic acid ( 1a ) or 2-oxo-2-hydroxy-5-amino-1,4,2-oxazaphospholidine-3-phosphonic acid ( 5 ) are obtained depending on the reaction conditions.     

Investigation of the effects of various parameters on the synthesis of oligopeptides in aqueous solution

Oligomerization efficiency of amino acids in aqueous solution has been compared under different conditions (temperature, activating agent, etc.) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 1,1^′-carbonyldiimidazole (CDI) as coupling agents. Glycine (H₂N-CH₂-COOH) and α-alanine (H₂N-CH(CH₃)-COOH) were chosen as α-amino acids and β-alanine (H₂N-CH₂-CH₂-COOH) as the β-amino acid. The coupling reaction between EDC and glycine was shown to occur but does not go to completion either at ambient temperature or at 70 °C. The presence of a carboxylic activating agent such as N-hydroxysuccinimide improves the EDC-mediated coupling reaction, and the amino acid structure (α- or β-) was shown to have an influence on the oligomerization efficiency, with β-alanine polymerisation being more efficient. These findings are explained by reference to the reaction mechanism.     

新法合成手性磷酸锌钠

对合成手性磷酸锌钠(NaZnPO₄·H₂O) (CZP)的新方法进行了研究,用Na₃PO₄·12H₂Oand ZnSO₄·7H₂O作为起始原料,聚乙二醇-400（PEG-400）为表面活性剂,通过一步低热固相反应得到了手性磷酸锌钠。用TG/DTG,XRD, TEM 及 SEM表征了产物。实验结果表明,Na₃PO₄·12H₂O与ZnSO₄·7H₂O的配比采用不同的p/Zn比（0.9～1.15）,在60 ℃下陈化不同的时间(2.0～8.0 h) 所得到的NaZnPO₄·H₂O,除了结晶度稍为不同之外,晶体的手性结构是一样的。对照实验的结果显示陈化温度及阴离子调控着NaZnPO₄·H₂O的对映体形态。即,若以ZnSO₄·7H₂O或Zn(NO₃)₂·6H₂O为锌源,当反应混合物在60 ^oC陈化时,生成产物的结构是空间群为 P6₁22 的第一种手性结构,当反应混合物在室温陈化时,生成产物的结构则是空间群为 P6₅22 的第二种手性结构。     

Preparation of Ammonium Cerium Phosphate via Low-heating Solid State Reaction and Its Catalysis for Benzyl Acetate Synthesis

Ammonium cerium phosphate was prepared with (NH₄)₃PO₄·3H₂O and Ce(SO₄)₂·4H₂O as raw materials and PEG‐400 as surfactant via a solid state reaction at low‐heating temperature. The characterization result of XRD indicates that the molecular formula of the product was (NH₄)₂Ce(PO₄)₂·H₂O. The synthesis of benzyl acetate was carried out with H₂SO₄/ammonium cerium phosphate as catalyst, and uniform experimental design as well as data mining technology was applied to the experiments, in which the effect of the reaction time, the molar ratio of acid to alcohol and the amount of catalyst on the conversion yield of acetic acid were studied. When benzalcohol was 0.10 mol, under the optimal reaction conditions, i.e. reaction time of 174 min, 2.02 of molar ratio of acid to alcohol and 0.5 g of catalyst, the esterification rate of acetic acid was 97.9%. The ammonium cerium phosphate had potential for industry application since it not only was feasible and simple in synthesis technics, but also had good catalysis activity for the synthesis of benzyl acetate.     

Formation of homo- and heteronuclear complexes of 1-hydroxyethylidene-1,1-diphosphonic acid with Mn<Superscript>II</Superscript> and Fe<Superscript>III</Superscript> in aqueous solutions

Systems based on 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), iron(iii)—HEDP and manganese(ii)—iron(iii)—HEDP, were studied by pH-potentiometry combined with mathematical modeling and NMR. Diverse and highly stable heteronuclear iron manganese complexes were found to exist in the heteronuclear system. The formation of the MnH₃L₂^3–, FeMnH₃L₂⁰, Fe₂MnHL₃^3–, and MnL^2– complexes was established. The relaxation efficiency coefficient REC₂ (relaxivity) of these complexes was evaluated at ~2000 mol^–1 s^–1 L. Therefore, these systems hold promise as MRI contrast agents.     

醋酸钯催化甲苯中无配体的 Suzuki 反应

 报道了一种甲苯中醋酸钯催化无配体的 Suzuki 反应体系. 以 K₃PO₄·7H₂O 为碱, 在该体系中可高效进行芳基溴代物和芳基硼酸的 Suzuki 反应, 且具有反应条件温和、无需惰性气体保护等特点. 在 n(ArBr) = 0.5 mmol, n(ArB(OH)₂) = 0.75 mmol, x(Pd(OAc)₂) = 1 mol%, n(K₃PO₄·7H₂O) = 1.0 mmol, v(甲苯) = 2 ml 的优化条件下, 4-溴硝基苯和苯硼酸在 75 °C 反应 5 min, 分离收率即达 99%, TOF 高达 1 188 h?1.     

Amidoalkylation of Phosphorus Trichloride with Acetamide and Functionalized Cyclic Ketones-Evidence of Dominating Role of Side-Reactions

Abstract

The course of the reaction between phosphorus trichloride, acetamide and ethyl oxoalkanecarboxylates was studied in terms of the production of side-products. When ethyl 2-oxocycloalkane- and 4-oxocyclohexanecarboxylates were used as substrates, not only mixtures of the expected products—aminophosphonocycloalkanecarboxylic acids and their ethyl esters but also the formation of three side-products, namely 1-aminocycloalkanephosphonic acids (products of decarboxylation of the latter ones) and 1-aminoethane-1,1-diphosphonic and 1-hydroxyethane-1,1diphosphonic acids (products of the reaction of substrate and solvent with phosphonylating agent) were observed. Ethyl 2-oxo-cyclooctanecarboxylate afforded the expected 2-amino-2-pohosphonocyclooctanecarboxylic acid in minute amounts. For comparison reactions of 1-butyloxocarbonyloxopiperidines afforded the desired aminopiperidinephosphonic acids in good yields and without formation of side-products.