Cyclohexene sulphide

As regards the dimethylcadmium-(7 )-(—)-3,3-diethyl-1,2-butanediol (1 1) catalyst, it was characterised by a lower stereoelectivity than the diethylzinc-(R)-(—)-3,3-dimethyl- 1,2-butanediol (1 1) catalyst in enantioasymmetric polymerisations of propylene sulphide, cA-2-butene sulphide and cyclohexene sulphide, but the elected chirality was opposite to that found for polymers obtained with the zinc-based catalyst [159]. 

Addition of SMe" " sources to the cation [CpW =CTolPR2 (COXPMe3) (R = Me, Ph) results in formation of the bicyclo[ 1.1.0]butane derivative 65.339 Addition of Seg or cyclohexene sulphide to CpW(CO)2 =CMeSMe results in tungstabicyclo[1.1.0]butane complexes.3 ... 

It should be noted that several procedures are available for the preparation of l-(trimethylsilyloxy)cyclohexene. In an original report252 it was prepared by heating a dimethylformamide solution of cyclohexanone under reflux with chlorotrimethylsilane in the presence of triethylamine. This procedure is generally satisfactory for aldehydes and symmetrical ketones, or ketones which can enolise in one direction only. The method described in Expt 5.214 employs lithium sulphide as an additive to increase the silylating power of the chlorotrimethylsilane, so that the reaction proceeds at room temperature acetonitrile is used as the solvent.253... 

Attempts have been made to estimate the concentration of active sites on a series of Co-Mo/AI2O3 catalysts by irreversible oxygen adsorption at 195 K on the reduced catalysts. There was a linear relationship between areal rate constants for cyclohexene hydrogenation and thiophen hds over the sulphided catalysts (623 K, 1 atm). For the most active catalyst [M0O3, 10.4% (Co + Mo), 0.10 Co/(Co + Mo), 0.17] the concentration of active... 

Benzyl phenyl sulphide, norbornene, cw-cyclooctene, and 4-vinyl-1-cyclohexene were obtained from Aldrich and (IS)-(-)-a-pinene from Fluka. Phenyl sulphide was prepared from benzene and sulphur chloride following the literature procedure[9]. Reference samples of sulphoxides and sulphones were prepared by oxidation of sulphides with sodium periodate[10] and hydrogen peroxide[ll] respectively. Reference samples of epoxides were made by following Kaneda et al.[ 2 procedure. Metal phthalocyanines[13] were prepared from appropriate metal salt, 1,2-dicyanobenzene with ammonium molybdate as catalyst and were characterized by elemental analysis. 

Similar results were obtained with 1-methyl cyclohexene which is a more accurate model of natural rubber than cyclohexene. However with low molecular weight polyisoprenes such as dihydromyrcene, geraniolene and squalene intramolecular reactions leading to the production of cyclic sulphides were also observed. 

Epoxy alcohols are the normal products of the [VO(acac)2]+(Me2C(CN)N a -catalysed oxidation of cyclic olefins by dioxygen however, cyclo-octene is oxidized exclusively to cyclo-octene oxide. The oxidation of sulphides and alkenes by peroxides with a [V(0)(acac)2] catalyst have been compared and the nature of the monoperoxovanadium(v) intermediate investigated. Complexation of a Cr(CO)3 unit to aromatic hydrocarbons enhances the benzylic positions towards attack by superoxide ion, e.g., diphenylmethane is readily converted into benzophenone. Metal porphyrin complexes ML4 continue to attract attention both as reversible oxygen-carriers (M = Fe) and oxidation catalysts (M = Mn, Fe, or Co ). For example [Mn (=0 IPh)(TPP)Cl] is believed to be involved in the oxidation of cyclohexene to cyclohexanol by PhIO in the presence of [Mn(TPP)]+ and a ferryl intermediate [Fe (0)L4] has been proposed in the oxygenation of triphenylphosphine with iron(ii) porphyrin. [M(TPP)]X (M=Mn, X = OAc M=Fe, X=C1 M = Co, X=Br) catalyses the epoxidation of styrene and cyclohexene with NaOCl under phase-transfer conditions. ... 

Formation.—A convenient and rapid synthesis of thiirans (yields 35— 90%) consists of treatment of epoxides with triphenyl- or tri-n-butyl-phosphine sulphide in the presence of acid. cis-Stilbene oxide gave exclusively cis-stilbene sulphide. (S)-(-)-Methylphenyl-n-propylphosphine sulphide gave, with a twofold excess of cyclohexene oxide, the (S)-(-)-oxide, indicating that this reaction proceeds with retention of configuration at phosphorus. " A mechanism involving two inversions was suggested for the conversion of 2a,3a-epoxycholestane into the 2, 3 3-epithio-isomer, as shown in Scheme 1. Epithiochlorohydrin is obtained by treatment of epichlorohydrin with di-(0-ethyl)dithiophosphoric acid and triethylamine. "... 

There have been a number of reports on the photochemical reaction between diazo-compounds and sulphides to form either stable or transient ylides. lllger et al. reported the isolation of a series of ylides from the reaction of dimethyl sulphide with substituted diazomethanes, such substituents being carbonyl, sulphonyl, or phosphoryl groups. Ando et of. described the reaction of diazo dimethyhnalonate with a series of sulphides but found that the yields of ylides varied considerably, much more so than for the thermal reaction, with the nucleophilicity of the sulphide. For example, dimethyl sulphide afforded an 88% yield of ylide (6a) while diphenyl sulphide afforded a 12% yield of ylide (6b). Repetition of the reaction with dimethyl sulphide but in the presence of cyclohexene indicated that the sulphide was about six times as reactive as the olefin toward the photochemically generated carbene. These reactions aU were assumed to occur by conversion of the diazo-compound into a singlet carbene, which attacked sulphur. However, it was found that (6a) also could... 

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