Synthesis of New Benzylic Di-, Tri-, and Tetraphosphonic Acids as Potential Chelating Agents

Abstract

New di-, tri-, and tetraphosphonic acids were synthesized starting from four o-hydroxymethyl phenol derivatives and obtained in three steps in good overall yield. The phosphonic acids were isolated and purified using semi-preparative C₁₈ HPLC column. The new compounds were characterized using different spectroscopic methods (¹H, ¹³C, and ³¹P NMR; ESI MS; and MSⁿ, IR).

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Tris(dialkylamino)phosphine Chalcogenide Complexes of Tin(IV) Chloride: A Multinuclear (31P, 77Se,and 119Sn) NMR Characterization

Abstract

Four octahedral complexes of the type SnCl₄.2L [L = (R₂N)₃P(E): E = Se; R = Me(1), Et(2) and E = S; R = Me(3), Et(4)] have been studied in solution by multinuclear (³¹P, ⁷⁷Se, and ¹¹⁹Sn) NMR spectroscopy. ³¹P and ⁷⁷Se NMR data were informative of changes associated with complex formation. The solution structure of the complexes was confirmed by their ¹¹⁹Sn NMR spectra that showed two triplet features for each complex, attributed to a mixture of the expected cis and trans isomers. The triplet signal is due to the coupling with two equivalent phosphorus atoms, consistent with an octahedral geometry around the tin center. In addition, density functional theory (DFT)/B3LYP calculations have been carried out to support the interpretations of NMR data. The results are discussed and compared with those reported for related complexes.

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The Synthesis of Novel S-, S,S-, S,S,S-, and N,S-Substituted Nitrodienes from Polyhalonitrodienes and Thiols

Abstract

The novel S-, S,S-, and S,S,S-substituted nitrobutadienes were synthesized from the reactions of 2-nitrobutadiene compounds with some thiols. The new N,S-substituted nitrobutadienes were obtained from the reaction of the mono-thiosubstituted butadienes with morpholine, thiomorpholine, homopiperazine, and piperazine derivatives. The structures of new compounds were determined by spectroscopic techniques.

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Planar Chiral and Achiral Arenido(triphenylphosphane)nickel(II) Complexes Containing N,O Bidentate Ligands: 19F, 1H,and 31P NMR Studies

Abstract

Planar chiral and achiral arenido(triphenylphosphane)nickel(II) complexes (arenido = mesitylenido, 2-toluenido) comprising electronically delocalised N,O chelating ligands were studied by ¹H and ¹⁹F NMR using 1D and 2D techniques. Results from complexes and corresponding ligands are discussed in the light of molecular structures obtained from X-ray diffraction.

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An Efficient and Convenient Protocol for the Synthesis of Thiazolidin-4-Ones

Abstract

Without a catalyst and under solvent-free conditions, 2,3-disubstituted-1,3-thiazolidin-4-one 5a–j derivatives were synthesized efficiently via the three-component reaction of aryl hydrazide, aromatic aldehyde, and mercaptoacetic acid. All the newly synthesized compounds were confirmed by IR, ¹H NMR, and ¹³C NMR spectroscopy and elemental analysis.

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New Dithiocarbamate Compounds from Organotin(IV)

Abstract

A series of new organotin(IV) dithiocarbamate compounds of type R_nSn (S₂CNR′R″)_4-n (n = 2, 3; R = dimethyl, dibutyl, diphenyl, triphenyl and tert-butyl; R′ = methyl, ethyl, benzyl; R″ = isopropyl, ethyl, ethanol) have been successfully synthesized. Elemental analysis showed that the percentage of the elements conformed to the general formula of these compounds. The important peaks of the infrared spectra for the stretching mode ν(C?N), ν(C?S), and v(Sn-S) for the compounds were observed in the area of 1440–1480 cm^?1, 940–1000 cm^?1, and 340–90 cm^?1, respectively. The ¹³C NMR spectra showed the most important peak for N¹³CS₂ chemical shifts were observed in the range 190–210 ppm. X-ray single crystal studies for several structures of these compounds showed that the chelating mode of the dithiocarbamate groups to the central tin atoms were either bidentate or anisobidentate.

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Synthesis and Characterization of Bidentate Cyclotriphosphazene Derivatives

Abstract

Three novel cyclotriphosphazene derivatives were designed. Title compounds were synthesized by the reaction of the dichlorocyclotriphosphazene derivative [N₃P₃Cl₂(O₂C₁₂H₈)₂] with the potassium salt of 4-hydroxybenzaldehyde, and subsequent reduction of aldehyde groups to alcohol groups using sodium borohydride. The bromination reaction was carried out using PBr₃ to give N₃P₃(O₂C₁₂H₈)₂ (OC₆H₄-p-CH₂Br)₂. This compound was employed in reactions with macrocyclic polyamide, imidazole, or morpholine to produce title compounds. The target compounds were characterized using ¹H NMR, ³¹P NMR, ¹³C NMR, IR, and electrospray ionization mass spectra (ESI-MS).

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Figures S1–S6.]

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Synthesis and Properties of 2-Alkylene/Dialkyl Dithiophosphato-2-oxo-1,3,2-dioxaphosphorinanes

Reactions of 2-chloro-2-oxo-1,3,2-dioxaphosphorinanes with ammonium alkylene/dialkyl dithiophosphates in a 1:1 molar ratio in refluxing benzene solution yields nonvolatile, yellow viscous liquids of the type (S)S(O) and (RO)₂ P(S)S(O) , respectively. [G = ? CH₂CH₂CHCH₃?,. ? C(CH₃)₂CH₂CHCH₃?,. ? CH₂C(CH₃)₂CH₂; R = i-C₃H₇, C₂H₅].

These compounds are hygroscopic and monomeric in nature. The newly synthesized derivatives have been characterized by physicochemical and spectroscopic techniques (IR, NMR [¹H&³¹P], and M.W).     

Synthesis and Biological Evaluation of Novel Phosphonates Derivatives of As Potential Antitumor Agents

Abstract

A series of dialkyl [2-(4,6-dimethoxypyrimidin-2-yloxy)benzamido](aryl) methylphosphonates derivatives were designed and synthesized. All the new compounds were identified by elemental analysis, IR, ¹H NMR, ³¹P NMR, and MS. Their antitumor activity against KB and CNE1 cells was examined. Some of the compounds showed potential antitumor activity, which provided some hints for further study of structure modification. In particular, the compounds 6i and 6j displayed more potent cytotoxic activities against KB in comparison with 5-FU.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Table S1]

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One-Pot Green Synthesis of 3'-(2-Aminobenzimidazolyl)-2-Phenyl Spiro[4H-Benzopyran-4,2'-Thiazolidin]-4-Ones and Acylation Using Trifluoroacetic Anhydride

Abstract

An expeditious one-pot synthesis of a novel heterocyclic system, 3′-(2-aminobenzimidazolyl)-2-phenyl spiro[4H-benzopyran-4,2′-thiazolidin]-4-ones, has been accomplished by condensing substituted hydrazinobenzimidazole, flavanone, and mercaptoacetic acid by conventional heating in ethanol or toluene, and in an ionic liquid, viz., 1-butyl-3-methyl-imidazolium hexafluorophosphate. Excellent yields (85%–90%) and higher purity are obtained in the ionic-liquid-mediated synthesis as compared with the conventional procedure (55%–60%). Further, these compounds were acylated with trifluoroacetic anhydride. The structures of the compounds were confirmed by IR, ¹H NMR, ¹³C NMR, mass spectral data, and elemental analysis. The compounds, upon evaluation for their antibacterial, antifungal, and insecticidal activities, exhibited excellent results.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Table S1, S2, and S3]

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Preparation,Properties and Complexation Behaviour of P,P-Di-tert. Butylphosphinothioic Amides

Abstract

Starting from tBu₂PCl, the title compounds tBu₂P(S)NHR′ (R′= Me Et, iPr, tBu) may be easily prepared according to With R′=tBu the amine has to be substituted by its Li-salt [tBuNH]^?Li^+.     

Reaction of Nucleophilic Polyhalogenalkylation in Two and Three-Component Systems

Abstract

The halophilic reactions of the derivatives of P^III R₃ P (R = R2N, Alk, Ar) with CCl₄, having preparative signifi-cance, are studied thoroughly. As far as the compounds of R₂PHlg type are concerned, at the beginning of our re-searches there was was an opinion that the interaction of R₂PHlg with CC14 cannot be possible because of the low nucleophility of phosphorus. We determined for the first time that diamidochlorophosphites 1 react with CC14 at the temperature 20°C and form the compounds 2, 3.¹      

Synthesis and Dynamic NMR Study of a Functionalized Sulfonamide Phosphonate Diester

Abstract

Protonation of the highly reactive 1:1 intermediate produced in the reaction between triphenylphosphite and activated acetylene by sulfonamide leads to a phosphonate ylide, which undergoes methanol elimination in the presence of moisture to produce a highly functionalized sulfonamide phosphonate diester. A dynamic nuclear magnetic resonance (NMR) effect is observed in the ¹H NMR spectra of this compound as a result of restricted rotation around the single C?N bond. The coalescence temperature was observed at T_C = 352.5 K, and the free energy of activation (ΔG^#) for this process is 75.6 ± 2 kJ.mol^?1.

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