Dialkylphosphonate and Thiophosphonate (Open Chain and Cyclic) Derivatives of Arsenic(III) and Tin(IV)

Abstract

Dialkylphosphonates¹ and -thiophosphonates² are versatile ligands but except for a few brief reports^3–9 the chemistry of their derivatives with group IV and V elements remains unexplored. The corresponding derivatives of cyclic phosphonates and thiophos-phonates¹⁰ are virtually unknown.     

Synthesis and characterization of some bis(cyclopentadienyl)titanium(IV) complexes with internally functionalized oximes(LH): sol–gel transformations of Cp2TiCl2, Cp2TiClL and Cp2TiL2 to nano‐sized anatase titania

Some bis(cyclopentadienyl)titanium(IV) complexes of the type [Cp₂TiCl_2?n{L}_n] {where, n = 1 or 2; L = ONC(R)Ar; R = H or CH₃ and Ar = C₅H₄N‐2, C₄H₃O‐2 or C₄H₃S‐2} have been synthesized by the metathetical reactions of Cp₂TiCl₂ with the sodium salt of internally functionalized oximes in 1:1 and 1:2 stoichiometry in anhydrous THF. All these red to brown colored solid derivatives have been characterized by elemental analyses, FT‐IR and NMR (¹H and ¹³C{¹H}) spectral studies. The FAB mass spectra of some representative derivatives indicate their monomeric nature. Oximato ligands in all the complexes appear to bind the titanium via N and O in a dihapto ( ‐N, O) manner in the solid state. Thermogravimetric curves of [Cp₂TiCl{ONC(CH₃)C₅H₄N‐2}] and [Cp₂Ti{ONC(CH₃)C₅H₄N‐2}₂] suggest the formation of hybrid materials CpTiO(Cl) and Cp₂TiO, respectively, as the final products at 900 °C under nitrogen atmosphere. Sol–gel transformations of Cp₂TiCl₂, [Cp₂TiCl{ONC(CH₃)C₅H₄N‐2}] and [Cp₂Ti{ONC(CH₃)C₅H₄N‐2}₂] yielded titania a–c, respectively, at low sintering temperature (600 °C). The powder XRD patterns, IR as well as Raman spectra of all these oxides indicate the formation of nano‐sized anatase phase. The SEM images of titania a–c indicate agglomers like surface morphologies. The absorption spectra of a–c exhibit an energy band gap in the range of 3.47–3.71 eV. Copyright © 2011 John Wiley & Sons, Ltd.     

Aluminum five‐ and six‐coordination in bis(acetylacetonato)aminoalkoxides

Reactions of bis(acetylacetonato)aluminum(III)‐di‐μ‐isopropoxo‐di‐isopropoxo aluminum(III), [(CH₃COCHCOCH₃)₂Al(μ‐OPrⁱ)₂Al(OPrⁱ)₂] with aminoalcohols, (HO R NR¹R²) in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene yielded binuclear complexes of the types [(CH₃COCHCOCH₃)₂Al(μ‐OPrⁱ)₂Al(O R NR¹R²)(OPrⁱ)] and [(CH₃COCHCOCH₃)₂Al(μ‐OPrⁱ)₂Al(O R NR¹R²)₂] (R   (CH₂)₃ , R¹ = R² = H; R =  CH₂C(CH₃)₂ , R¹ = R² = H; R =  (CH₂)₂ , R¹ = H, R² =  CH₃; and R   (CH₂)₂ , R¹ = R² = CH₃), respectively. All these compounds are soluble in common organic solvents and exhibit sharp melting points. Molecular weight determinations reveal their binuclear nature in refluxing benzene. Plausible structures have been proposed on the basis of elemental analysis, molecular weight measurements, IR, NMR (¹H, ¹³C, and ²⁷Al), and FAB mass spectral studies. ²⁷Al NMR spectra show the presence of both five‐ and six‐coordinated aluminum sites. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:518–522, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10184     

O-Alkyl Trithiophosphate Derivatives of Triorganotin(IV) and S-Alkyl Trithiophosphate Derivatives of Diorganotin(IV) Chloride

Reactions of triorganotin chlorides with potassium salt of O-alkyl trithiophosphate [ROP(S)(SK)₂; R = Me, Prⁱ, Ph] in 2:1 molar ratio in anhydrous benzene yield triorganotin O-alkyl trithiophosphate of the type ROP(S) [SSnR′₃]₂ R = Me, Prⁱ; Ph, R′ = Prⁿ, Buⁿ, Ph] which are found to be monomeric in nature. These complexes are soluble in common organic solvents. Similar reactions of diorganotin chloride with dipotassium salt of S-alkyl trithiophosphate yield diorganotin-S-alkyl trithiophosphate of the type [(RS)P(O)S₂]₂SnR′₂; R = Me, Prⁱ; R′ = Me, Et, Ph, which also are found to be monomeric in nature and are soluble in common organic solvents. The newly synthesized derivatives have been characterized by physicochemical and spectroscopic techniques, IR, NMR (¹H, ³¹P, and ¹¹⁹Sn).     

Eggshell Nanosheets: Synthesis,Properties, and Their Forensic Applications in Latent Friction Ridges Development

Since waste materials are used to identify, individualize, and evaluate evidence like fingerprints, palmprints, footprints, etc. that are found at a crime scene, they have a substantial impact on the field of forensic science. Many waste powders have recently been employed in fingerprint recognition. Nanosheets made up of eggshells have been put forward as an application in friction ridge development. Eggshell is a biochemical substance made up of chemical compounds like calcium carbonate, which is considered as a waste product. For the formation of an eggshell nanosheet (ESN), shells are dried and crushed into a fine powder and to get this powder in the form of a nanosheet, the Ball milling technique is used. The synthesis of pure ESN is confirmed by Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) techniques. The size of nanosheets ranged from 30 to 90 nm as shown in SEM images. Developed powder is then used for the application of fingerprint development and it provides excellent results on all porous, non-porous, and semi-porous surfaces. Thus, this newly synthesized ESN powder can be used as a significant powder method in latent fingerprint technology.     

Dialkyl (Alkylene) Dithiophosphate Adducts of Anhydrous Stannous Chloride: Synthesis,Characterization, and Biological Activities

Abstract

Dialkyl (alkylene) dithiophosphate adducts of stannous chloride were synthesized by the reaction of anhydrous tin(II) chloride (SnCl₂) and dialkyl (alkylene) dithiophosphoric acid in a 1:1 molar ratio, under anhydrous reaction conditions, below 5 °C in a closed vessel. The newly synthesized adducts were characterized by physicochemical and spectroscopic techniques [FT-IR, NMR (¹H, ³¹P, and ¹¹⁹Sn), and mass spectrometry]. Coordination modalities have indicated a donor–acceptor interaction between sulfur and tin(II) moieties, where tin(II) acts as a Lewis acid. The adducts were found to have significant antibacterial activity against Escherichia coli and Pseudomonas aeruginosa, and antifungal activity against Aspergillus niger and Candida albicans.

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.     

Synthesis and Properties of Alkylene (Dialkyl) Dithiophosphate Derivatives of Thionyl Chloride

Alkylene (dialkyl) dithiophosphate derivatives of thionyl chloride of the general formula (S)SS(O)Cl and (RO)₂(S)SS(O)Cl where G = ─ CH₂(CH₃)₂CCH₂─, ─ CH₂CH₂CH(CH₃)─, ─ C(CH₃)₂CH₂CH(CH₃)─ and R = i-C₃H₇, have been synthesized by reacting thionyl chloride with alkylene/dialkyl dithiophosphates in a 1:1 molar ratio in refluxing benzene. A similar reaction in a 1:2 molar ratio yields the corresponding products of the type (S₂)₂S═O and [(RO))₂PS₂]₂S═O. It is interesting to note here that the sulfur atom of the thionyl chloride has been retained in the product, which is evidenced by sulfur analysis. The products thus obtained are light yellow colored semi solid (1:1 products) and orange colored liquids (1:2 products); and are soluble in common organic solvents. These new compounds have been characterized by elemental analysis, molecular weight measurements, and spectroscopic [IR and NMR (¹H and ³¹P)] studies. These compounds are found to be biologically active against bacteria S.aureus and E.coli.     

DIALKYL THIOPHOSPHONATE DERIVATIVES OF TRIORGANOTIN(IV)

Abstract

The reaction of triorganotin chlorides with sodium dialkyl thiophosphites proceeds to completion on refluxing the reactants in a 1:1 molar ratio for about ten hours. Similar reactions of triorganotin chloride with dialkyl thiophosphonate do not give comparable yields in the presence of triethylamine. The products formed are colorless volatile liquids having pungent odour, are miscible with common organic solvents and are found to be monomeric. Exposure of these compounds to atmospheric oxygen the thiophosphite [Sn-S-P] linkage was oxidized to a thiophosphate [Sn-O-P(S)] linkage. These complexes have been characterized by elemental analyses, molecular weight determination, IR, ¹H NMR and ³¹P NMR spectral data.     

Kinetic studies on the mechanism of the relative catalytic activities of surfactants in the oxidation of amino-acids by chloramine-T

The kinetics of oxidation of amino-acids by chloramine-T in the presence of two different surfactants (cationic and anionic surfactants) in acidic medium has been studied. The kinetic results show that the reaction is fractional and first order with respect to substrate and oxidant respectively. The influence of halides, ionic strength and solvent on the rate has been studied. The effect of surfactants on the reaction show that the reaction velocity is highly sensitive to the variation of surfactant concentration. The micelle-substrate binding constant (K) and co-operativity index have been calculated indicating the stability of the catalyst substrate micelles (complex) so formed. A probable reaction path has been suggested and discussed in the light of various experimental results and findings.     

Pharmacoinformatics-based identification of transmembrane protease serine-2 inhibitors from Morus Alba as SARS-CoV-2 cell entry inhibitors

Molecular Diversity - Transmembrane protease serine-2 (TMPRSS2) is a cell-surface protein expressed by epithelial cells of specific tissues including those in the aerodigestive tract. It helps the...