A CONVENIENT SYNTHESIS OF N-PHENYLSULFONYL-S-ARYL-S-CHLOROSULFOXIMINES

Abstract

N-Phenylsulfonyl-S-phenyl-S-chlorosulfoximine and N-phenylsulfonyl-S-(p-nitrophenyl)-S-chlorosulfoximine are prepared in 40–50% yields from corresponding disulfides, chlorine and N,N-dichlorobensenesulfonamide.

The suggested procedure is of advantage because it uses the stable and simply purified iminating reagent (N,N-dichlorobensenesulfonamide) and excludes the isolation of unstable reaction intermediates (sulfinyl chlorides).     

Interconversions of the silylene-to-silene and germylene-to-germene types: direct spectroscopic studies and calculations

The recent advances in spectroscopic and quantum-chemical studies of carbene-to-olefin isomerization of carbene analogs of Group 14 elements are discussed. Primary attention is devoted to the use of matrix isolation spectroscopy, whose successful combination with modern calculation techniques has resulted in the first spectroscopic characterization of a number of novel short-lived silylenes and germylenes and their structural isomers with unsaturated Si=C, Ge=C, and Si=O bonds. Based on invited lecture given by Professor Dr. V. N. Khabashesku at the Sixth International Conference on Chemistry of Carbenes and Related Intermediates (May 28–30, 1998, St. Petersburg, Russia). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2027–2039, November, 1999.     

Covalent sidewall functionalization of single-walled carbon nanotubes by amino acids

Single-walled carbon nanotubes (SWNTs) with amino acids covalently attached to their side walls, viz., “nanotube-aminoacids,” have been prepared starting from colloidal solutions of fluorinated SWNTs (F-SWNTs) and amino acids in o-dichlorobenzene and heating at 80–150 °C in the presence of pyridine. The syntheses were carried out with the F-SWNTs of approximately 2: 1 (C: F) stoichiometry and several natural α-aino acids with both pro-tected and unprotected carboxyl groups, such as glycine ethyl ester hydrochloride, L-serine ethyl ester hydrochloride, l-cysteine, and trans-4-hydroxy-l-proline. The nanotube-aminoacids have been characterized by Raman and FTIR spectroscopy, atomic force, scanning, and transmission electron microscopies, and thermal gravimetric analysis (TGA). Based on TGA data, the degree of sidewall functionalization in the synthesized SWNT derivatives was estimated to be in the range from one of 32 to one of 8 carbon atoms, depending on the amino acid nature and reaction conditions used. The amino acid-functionalized SWNTs, prepared in this work by simple and inexpensive one-step method, can be valuable precursors for peptide synthesis and targeted drug delivery, design and fabrication of nanocomposites and fibers, and other biomedical and engineering applications. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1035–1043, May, 2008.     

Polyhedral carbon nanoparticles at high pressures

The solid-phase transformations of polyhedral nanoparticles at a pressure of 8.0 GPa and various temperatures have been investigated by X-ray diffraction, small-angle X-ray scattering, and transmission electron microscopy. It has been found that the graphene layers of the inner cavities of polyhedral particles are transformed into onion-like structures at temperatures above ～1000°C. This transformation gives rise to the formation of hybrid-type sp2 carbon nanoparticles, which combine the outer polyhedral shape with the quasispherical onion-like core. Polyhedral nanoparticles smaller than ～40 nm are completely transformed into onion-like particles at 1600°C.     

Synthesis of carbon nanotube—nanodiamond hierarchical nanostructures and their polyurea nanocomposites

Hierarchical carbon nanostructures (HCNs) comprising functionalized nanodiamond particles (ND) covalently bonded to carbon nanotubes (CNTs) through urea or ethylene diamine linkers were synthesized using wet chemistry technique. Atomic force microscopy, transmission electron spectroscopy, and scanning electron spectroscopy reveal the pearl-necklace-like morphology of new HCNs with up to 50% of the CNT surface decorated by ND particles. Nanocomposites fabricated using polyuria/polyurethane hybrid polymer matrix and 0.2 wt.% of HCNs as a reinforcing filler show a 64% increase in tensile and elongation strength at break relatively to neat polymer.     

Generation and IR spectroscopic study of benzyl radical

The benzyl radical C₆H₅CH₂ has been obtained by gas phase pyrolysis of two different precursors, benzyl bromide and dibenzyl, and studied in an argon matrix at 12 K by IR spectroscopy. Similarly, the deuterosubstituted benzyl radicals, C₆H₅CD₂ and C₆D₅CH₂, have been investigated. The assignment of the IR bands of the benzyl radical and its deuteroanalogs to fundamental modes and a calculation of the valence force field have been performed. The obtained data give evidence of sp² hybridization of the methylene carbon atom and delocalization of the electron density between the ring and the CH₂ group, and are in good agreement with the planar structure of the radical.These results were presented for the first time in O. M. Nefedov's plenary lecture at X IUPAC Conference on Physical Organic Chemistry (Haifa, Israel, August 1990).Deceased July, 1986.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1499–1502, August, 1993.     

Fluorinated nanodiamond as a wet chemistry precursor for diamond coatings covalently bonded to glass surface

The chemical reaction between fluoro-nanodiamond (F-ND) powder, solubilized in o-dichlorobenzene, and a glass surface, functionalized with the silane coupling agent, 3-aminopropyltriethoxysilane (APTES), was found to proceed under heating at 130 degrees C for 24-40 h and to result in covalent bonding of F-ND particles to a glass substrate, forming a 10-40 nm thick nanocrystalline film. The observed process presents a novel and cost-effective approach to fabrication of diamond coatings on glass by using wet chemistry instead of CVD and can be extended to other materials.