Showing papers on "Cyclohexene published in 1985"

Conversion of alkenes to 1,2-diazides and 1,2-diamines

Abstract: Azidation par NaN 3 en presence d'acetate de manganese III, des decene-1, octene-4, cyclohexene. Obtention de diazides-1,2 dont la reduction donne les diamines-1,2

Boron trifluoride catalyzed addition of disulfides to alkenes

Abstract: Addition de dimethyl-, diethyl-, diisopropyl-, di-t-butyl- et (methylphenyl) disulfures sur des butenes-2, cyclopentadiene, cyclohexene et butadiene-1,3

Thermal and photochemical catalytic dehydrogenation of alkanes with [IrH2(CF3CO2)(PR3)2](R = C6H4F-p and cyclohexyl)

Abstract: [IrH2(CF3CO2)(Pcy3)2](cy = cyclohexyl) catalyses the photochemical dehydrogenation of cyclo-octane both in the presence and absence of a hydrogen-acceptor.

Mechanistic considerations in the photodisproportionation of .mu.-oxo-bis((tetraphenylporphinato)iron(III))

Abstract: Formation du complexe ferreux (FeTPP) et du complexe (Fe(IV)DTPP). Oxydation catalytique d'olefines par photolyse de (FeTPP) 2 O en presence de O 2

Reversed Stereochemical Course of the Michael Addition of Cyclohexanone to β‐Nitrostyrenes by Using 1‐(Trimethylsiloxy)cyclohexene/Dichloro(diisopropoxy)titanium. Preliminary Communication

Abstract: Induced by a stoichiometric excess of dichloro(diisopropoxy)titanium, 1-(trimethylsiloxy)cyclohexene and p-substituted β-nitrostyrenes (Y = H,CH3,CH3O,CN) combine in CH2Cl2 solution at −90° preferentially with relative topicity ul – opposite to the corresponding reaction of enolates or enamines. The primary products are the bicyclic nitronates 3–5 which can be separated, and which are cleaved by KF in MeOH to give the aryl(nitroethyl)-substituted cyclohexanones 1 and 2 (Tables 1 and 2, two typical procedures are given). The major products (2:1 to 4:1) are the hitherto not readily available diastereoisomers 2 of l-configuration. Instead of being solvolyzed, the bicyclic nitronate 5 can be used for nitroaldol additions (6) and for [3 + 2]-dipolar cycloadditions (7), diastereoselectively furnishing products with 4 asymmetric C-atoms (not counting acetal centers). The Michael addition described here is yet another example of an ul-combination of trigonal centers induced by Lewis acids, overriding the influence of the configuration of the donor component.

Platinum-alcenylcyclohexene complex as a hydrosilylation catalyst and process for its preparation

Abstract: The present invention relates to a method for preparing a hydrosilylation catalyst platinum-olefin complex, which comprises reacting a platinum on a basic compound of halide selected from at least one carbonate or bicarbonate of alkali metal or alkaline earthy in the presence of an olefinic ligand chosen from an alkenyl cyclohexene of formula wherein R Using the platinum complex as alcenylcyclohexene hydrosilation catalyst in the organo-polysiloxane compositions.

Direct evidence for bromine-olefin charge-transfer complexes as essential intermediates of the fast ionic addition of bromine to cyclohexene

Abstract: La reaction est etudiee spectrophotometriquement par la technique de l'ecoulement stoppe avec ou sans addition de cyclohexane dans le milieu reactionnel. Mise en evidence d'intermediaires ioniques

Copper(I) complexes with unsaturated small molecules. Synthesis and properties of monoolefin and carbonyl complexes

Abstract: Preparation de complexes de Cu(I) carbonyle ou non, mixtes ou non. Structures etudiees par IR et RMN

Organoaluminum-induced addition of polyhalomethane to olefins

Abstract: A mild procedure for the trimethylaluminum-induced addition of polyhalomethane to olefins has been described.

Hydrophobic vitamin B12. IV. Addition reactions of alcohols to olefins as catalyzed by hydrophobic vitamin B12 derivatives

Abstract: Addition reactions of alcohols to olefins were catalyzed by hydrophobic vitamin B12 derivatives under aerobic irradiation conditions at the room temperature range. Ethyl vinyl ether, 1-pentene, and cyclohexene were adopted as olefins, while heptamethyl methylaquacobyrinate perchlorate and heptamethyl cyanoaquacobyrinate perchlorate were used as the starting complexes. Heptamethyl cobyrinate, which was generated from heptamethyl methylaquacobyrinate perchlorate by aerobic photolysis, is an appropriate catalyst for investigation of the reaction mechanism because the alkylated complex having the cobalt–carbon σ-bond, the reaction intermediate, has a long lifetime sufficient for its identification in the dark. On the other hand, heptamethyl cyanocobyrinate, which was derived from heptamethyl cyanoaquacobyrinate, is superior to heptamethyl cobyrinate as the catalyst for the addition reaction. The reaction proceeds via light-promoted decomposition of the alkylated complex, and the catalyst is regenerated upon a...

Sulfur-directed Diels-Alder reactions. Synthesis of 1,5-disubstituted cyclohexene derivatives

Abstract: On prepare l'acetyl-5 methyl-1 cyclohexene par addition de Diels Alder de la methylvinylcetone avec le methyl-3 phenylthio-2 butadiene-1,3

Preparation and some reactions of 4- and 5-aryl-4,5-dihydropyridazin-3(2H)-ones

Abstract: Efficient preparations of 4- and 5-phenyl-4,5-dihydropyridazin-3(2H)-ones have been developed, the main reactions of these compounds have been studied, and the synthetic routes have been used to give analogues with substituents in the phenyl rings.In the best synthesis of the 4-phenyldihydropyridazinone (72% overall yield) the product was obtained from phenylacetic acid by three simple stages. This approach was applied in preparations of the 2- and 4-hydroxyphenyl compounds and, in conjunction with a recent method for amine protection, the 4-aminophenyl analogue. A four stage synthesis starting from benzaldehyde gave the 5-phenyl-dihydropyridazinone in 47% overall yield; hydroxybenzaldehydes were similarly converted into 5-(allyloxyphenyl)dihydropyridazinones.Oxidation to phenylpyridazinones occurred more readily with the 4- and 5-phenyldihydropyridazin-ones than with the 6-phenyl isomer. The 4- and 5-dihydropyridazinones were smoothly reduced to tetrahydropyridazinones by hydrogenation over platinum but were unaffected by palladium in the presence of hydrazine or cyclohexene.

Carboxamide and carbalkoxy group directed stereoselective iridium-catalyzed homogeneous olefin hydrogenations

Abstract: Carboxamide and carbalkoxy substituents are capable of directing the stereochemical course of homogeneous (Ir(cod)py(PCy/sub 3/))PF/sub 6//CH/sub 2/Cl/sub 2/-catalyzed hydrogenation (1 atm) of cyclohexenes. Data are presented to demonstrate that the carboxamide group is a superior stereocontrol agent for this hydrogenation of cyclohexene rings. 14 references, 1 figure, 1 table.

Catalytic Epoxidation of Olefins with t-Butyl Hydroperoxide in the Presence of Polymer-supported Vanadium(V) and Molybdenum(VI) Complexes

Abstract: Oxovanadium(V) and oxomolybdenum(VI) ions have been incorporated into cross-linked polystyrene resins functionalized with iminodiacetic acid or diethylenetriamine derivatives. The polymer complexes have been used as catalysts in the epoxidation of olefins with t-butyl hydroperoxide. Vanadium(V) complexes promote epoxidation of allylic alcohols in a highly regioselective manner, e.g., 2,3-epoxide has been preferentially obtained in 98% selectivity from (E)-geraniol at 80 °C. The catalytic activity of the vanadium(V) complexes is generally higher than that of the molybdenum(VI) complexes in the epoxidation of allylic alcohols whereas an opposed trend holds for the epoxidation of cyclohexene. Life time of catalysts have been examined by repeated use of the complexes in the epoxidation of (E)-geraniol at 80 °C in benzene. Approximately 15–25% of vanadium has been leaked out of the polymer beads on five time recycles leading to the decrease in the yield of 2,3-epoxide from initial value of 98% to 95–93%. Neith...

Competetive photochemical .sigma.2 + .pi.2 addition and electron transfer in the N-methylphthalimide-alkene system

Abstract: Obtention de benzoazepine-2 diones-1,5 diversement substituees Mecanisme faisant intervenir une paire d'ions radicalaires