- A process for the preparation of isoflavones propanethiol
-
The invention discloses a method for synthesizing isopropyl mercaptan from propylene and hydrogen sulfide. According to the method, a heat insulation type fixed bed reactor is used and isopropyl mercaptan is synthesized of hydrogen sulfide and propylene in the presence of a solid acid catalyst according to a continuous production process. The method disclosed by the invention has the advantages that the reaction conditions are easy to control, the yield is high, the process is simple, and the environmental pollution is reduced.
- -
-
Paragraph 0052; 0053
(2017/04/03)
-
- Hydrogenation of sulfoxides to sulfides under mild conditions using ruthenium nanoparticle catalysts
-
The first demonstration of the hydrogenation of sulfoxides under atmospheric H2 pressure is reported. The highly efficient reaction is facilitated by a heterogeneous Ru nanoparticle catalyst. The mild reaction conditions enable the selective hydrogenation of a wide range of functionalized sulfoxides to the corresponding sulfides. The high redox ability of RuO x nanoparticles plays a key role in the hydrogenation.
- Mitsudome, Takato,Takahashi, Yusuke,Mizugaki, Tomoo,Jitsukawa, Koichiro,Kaneda, Kiyotomi
-
supporting information
p. 8348 - 8351
(2014/08/18)
-
- PROCESSES OF MAKING AND CRYSTALLINE FORMS OF A MDM2 INHIBITOR
-
The present invention provides processes for making 2-((3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-1-((S)-1-(isopropylsulfonyl)-3-methylbutan-2-yl)-3-methyl-2-oxopiperidin-3-yl)acetic acid as well as intermediates and processes for making the intermediates. Also provided are crystalline forms of the compound and the intermediates.
- -
-
Paragraph 069; 0270; 0271
(2015/01/06)
-
- Anchimeric assistance of the sulfinyl group in the hydrolysis of cyano groups: A new mild method for the reduction of sulfoxides
-
Conditions to achieve reductive hydrolysis of β-cyanosulfoxides into their corresponding β-sulfenylamides are reported. The anchimeric assistance of the sulfinyl oxygen in the hydrolysis of the cyano group is proposed to explain the mild condition required to achieve it and several proofs supporting this assumption are indicated. From these results a new mild method to transform sulfoxides into sulfides has been developed.
- Garcia Ruano, Jose L.,Martin Castro, Ana M.,Rodriguez Ramos, Jesus H.
-
p. 4569 - 4572
(2007/10/03)
-
- Boron trifluoride monohydrate catalyzed one-flask preparation of sulfides from carbonyl compounds with thiols and triethylsilane
-
Boron trifluoride monohydrate catalyzed thiolation of aldehydes and ketones with thiols and triethylsilane to the corresponding sulfides was carried out in good to excellent yields.
- Olah,Wang,Trivedi,Prakash
-
p. 465 - 4466
(2007/10/02)
-
- Electronic and steric effects in the dissociative displacement of thioethers from mixed phenyl(thioether)platinum(II) complexes
-
A series of compounds of the type cis-[PtPh2L2], where L encompasses a wide range of thioethers of different steric and electron-donating characteristics, have been prepared and characterized. Most of these monomeric compounds exist in solution in equilibrium with the sulfur-bridged dimer [Pt2Ph4(μ-L)2] and the free thioether. Addition of small amounts of ligand in solution allows the stabilization of the monomeric form. Kinetic studies of the displacement of the thioethers with 2,2′-bipyridine (bpy) to yield [PtPh2(bpy)] in CH2Cl2 at 298.16 K, carried out in the presence of sufficient excess of [L] and [bpy] to ensure pseudo-first-order conditions, showed that the reactions follow a bivariate nonlinear rate law kobsd = a[bpy]/(b[L] + [bpy]) + c[bpy], which has the same form as that of similar systems for which a dissociative mechanism has been proposed. The reactivity decreases linearly with increasing σ-donor ability of the leaving thioether, with bulky substituents on sulfur playing an accelerating role. The relative sensitivities of the dissociative and associative processes to the inductive effects of the leaving group are compared and related to the degree of lengthening and weakening of the bond with the metal produced by the trans-activating group.
- Alibrandi, Giuseppe,Minniti, Domenico,Scolaro, Luigi Monsù,Romeo, Raffaello
-
p. 1939 - 1943
(2008/10/08)
-
- THERMODYNAMICS OF S THEREFORE S2 sigma /1 sigma * THREE-ELECTRON BONDS AND DEPROTONATION KINETICS OF THIOETHER RADICAL CATIONS IN AQUEOUS SOLUTION.
-
These experiments on the determination of K//1 and the associated rate constants were conducted at various temperatures and thus provided for the first time experimentally determined thermodynamic parameters ( DELTA H** does not equal and DELTA S** does not equal ) for the unimolecular dissociation of the three-electron bond. This in turn will allow an experimental estimate for the sulfur-sulfur bond strength in (R//2S therefore SR//2)** plus . Up to now only a theoretical ab-initio value has been published, namely 130 kJ mol** minus **1 for the simplest congeneric species with all R equals H. The kinetic and thermodynamic results substantiate previous conclusions on the electronic structure and relative stability of S therefore S bonded radicals and corroborate some theoretical calculations.
- Moenig,Goslich,Asmus
-
p. 115 - 121
(2007/10/02)
-
- Reactivity of Chalcogen Cluster Polycations
-
The chalcogen polycations S8(AsF6)2, S19(HS2O7)2, and Se4(HS2O7)2 are powerful oxidants entering into electron transfer reactions with hydrocarbons, aromatic compounds, and halides.
- Rosan, A. M.
-
p. 377 - 378
(2007/10/02)
-
- RADICAL CATIONS OF ORGANIC SULPHIDES AND DISULPHIDES FORMED BY RADIOLYSIS: AN ELECTRON SPIN RESONANCE STUDY
-
Exposure of dilute solutions of various organic sulphides in fluorotrichloromethane at 77 K to 60Co γ-rays gave species identified by their e.s.r. spectra as the parent radical cations.The average β-proton coupling (R2CHS.R)+ of ca. 20 G is about half that for the corresponding ether cations, indicating greatly reduced ?-? delocalisation.However, the spread of g-values (ca. 2.032, 2.015, 2.00) is much greater than that for the ether cations.These cations readily react with other disulphide molecules to form (R2S.-SR2)+ dimer cations.The spectrum for tetrahydrothiophene (tetramethylene sulphide) exhibits a large coupling to two axial protons (ca. 42 G) and two equatorial protons (ca. 19 G), the coupling constants again being about half those for tetrahydrofuran cations.However, conformational inversion did not occur below the softening point of the solids (ca. 160 K) in marked contrast with the ether cations.The three-and four-membered ring cations (ethylene and trimethylene sulphide cations) gave very similar spectra with gx = gy, and four equivalent protons having an isotropic coupling of ca. 31 G.Thus their structures are similar to the normal R2S.+ cations, the equivalence of the g-values being interpreted in terms of effective C-S-C bond angles (θ) close to 90 deg.This, in turn, implies that θ > 90 deg for the unconstrained cations.It is noteworthy that the ethylene oxide (oxirane) cation exhibits a smaller coupling to its four protons (16 G).This implies a drastic change in structure for the oxirane cation which is clearly not the case for the sulphur analogue.Disulphides of structure R-S-CH2-S-R form cyclic ?* radicals with weak S-S bonding, in marked contrast with the oxygen analogues (acetal cations) which have ?-structures conferring very high spin-density onto the CH2 protons.Other molecules containing two RSR units form similar cyclic ?* radicals.Persulphides of structure RS-SR readily give the ?-cations (RS.SR)+, characterised by g-values in the region of 2.035, 2.018, 2.002.The smaller range of g values for (PhS.-SPh)+ cations is interpreted in terms of ca. 30percent spin-delocalisation into both the benzene rings.
- Rao, Ramakrishna D. N.,Symons, M. C. R.,Wren B. W.
-
p. 1681 - 1688
(2007/10/02)
-
- Chemical Conversions using Sheet Silicates: Novel Intermolecular Eliminations of Hydrogen Sulphide from Thiols
-
Aliphatic primary and secondary thiols react in the interlamellar layers of ion-exchanged montmorillonite catalysts to produce dialkyl sulphides via intermolecular elimination of hydrogen sulphide; similar processes result in the production of diphenyl sulphide from benzenethiol and poly(phenylenemethylene) from α-toluenethiol.
- Ballantine, James A.,Galvin, Robert P.,O'Neil, Robert M.,Purnell, Howard,Rayanakorn, Mongkon,Thomas, John M.
-
p. 695 - 696
(2007/10/02)
-
- Reactions of Polychlorobenzenes with Alkanethiol Anions in HMPA. A Simple, High-Yield Synthesis of Poly(alkylthio)benzenes
-
Reactions of the isomeric trichlorobenzenes and tetrachlorobenzenes and of pentachloro- and hexachlorobenzene with an excess of the sodium salt of the isopropanethiol, in HMPA, afforded the products of complete displacement of all the chlorine atoms present in the molecule.Similar substitutions were also obtained with EtSNa.The reactions with MeSNa were in some cases complicated by the competitive nucleophilic attack at the methyl group of the initially formed aryl methyl thioethers which are thus demethylated to afford thiophenols.
- Testaferri, Lorenzo,Tingoli, Marco,Tiecco, Marcello
-
p. 4376 - 4380
(2007/10/02)
-
- Electrochemical Reduction of Alkyl Aryl and Dialkyl Trithiocarbonates
-
Electrochemical reduction in aprotic medium of alkyl aryl trithiocarbonates (1a-c) in the presence of an alkylating agent gives tetraalkyltetrathioethylenes (2a-c); under similar conditions dialkyl trithiocarbonates (3a-c) also form 2, but the reaction is complicated by the ability of 3 to act as an alkylating agent.The mechanisms of the reactions are discussed on the basis of the preparative and cyclic voltammetric results.
- Falsig, Mogens,Lund, Henning
-
p. 545 - 550
(2007/10/02)
-
