Alkenes, cyclic => alkene-halides

Alkenes, Cyclic Alkenes, and Dienes Alkenes, Cyclic Alkenes, and Dienes Ethylene Propylene Alkyl Halides Alkynes Aluminum Americium Amides Amides Carbofuran Dimethyl Acetamide Amines Antimony... 

Ethylbenzene under Benzene and Monosubstituted Benzene Hydrocarbons Ethyl Chloride Chloroethane under Saturated Alkyl Halides Ethyl Lactate Hydroxypropanoic Acid, Ethyl Ester under Esters Ethylene under Alkenes, Cyclic Alkenes, and Dienes... 

Alkenes react with acyl halides or acid anhydrides in the presence of a Lewis acid catalyst. The reaction works better with cyclic alkenes than with acyclic ones. 

When an alkene is used in the alkylation of arenes, metal halides with hydrogen halide or water as cocatalyst, protic acids, and acidic oxides can be used as catalysts. Both linear and cyclic alkenes are used in alkylations. Alkylation with alkenes is usually preferred in industry because the processes are simpler and olefins are readily and cheaply available in pure form from petroleum refining processes. 

Electrophilic ring closure of aryl-substituted compounds such as alkenes, halides, alcohols, and carbonyl compounds called cyclialkylation can be induced by conventional Friedel-Crafts catalysts309 and by superacids. Examples are also known in which an intermolecular alkylation step is followed by intramolecular alkylation of the intermediate to furnish a cyclic product. 

As the Wittig reaction forms both tt and cx-bonds, the disconnection is right across the middle of the alkene giving a choice of starting materials. So with the exo-cyclic alkene 26, very difficult to make by elimination methods, we could use formaldehyde or cyclohexanone as the carbonyl component with either phosphonium salt 25 or 28. It is a matter of personal choice whether you draw the ylid, the phosphonium salt or the alkyl halide at this stage. 

Much work has gone into the optimization of results with functionalized alkenes. In the reaction of cyclic alkenes, ds-decomposition of organopalladium halide-alkene complex gives -palladium complex 41. This subsequently undergoes syn-p-hydride elimination since only one such hydrogen is available, deconjugation to 3-substituted alkenes should... 

An alternative procedure for the preparation of /J-alkoxy selenides involves treatment of cyclic or acyclic alkenes with phenylselenenyl cyanide in the appropriate alcohol in the presence of catalytic amounts of copper(ri) or nickel(ll) halides. The reaction using methanol as the alcohol with cyclic alkenes is tram stereoselective giving /1-methoxy selenides 23 usually in high yield34. 

Acyl halides have been added to many alkenes, in the presence of Friedel-Crafts catalysts, although polymerization is a problem. The reaction has been applied to straight-chain, branched, and cyclic alkenes, but to very few containing functional... 

Blaser and Spencer used aroyl halides in place of aryl halides, with aroyl chlorides being of specific interest as ubiquitous, relatively cheap compounds ( Blaser reaction ) [24], This latter reaction is normally conducted in aromatic solvents phosphines are not used here as catalyst ligands since they fully inhibit the reaction. In the same way, benzoic acid anhydrides can be used as the aryl source in combination with PdCl2 and catalytic amounts of NaBr [79]. In this reaction, one of the arenes is used in the coupling reaction by elimination of CO, whereas the other benzoate serves as the base. The benzoic acid thus formed can easily be recycled into the anhydride. The use of aryl and vinyl triflates according to Cacchi [25] and Stille [26] extends the scope of the Heck coupling to carbonyl compounds phenol derivatives act via triflate functionalization as synthetic equivalents of the aryl halides. The arylation of cyclic alkenes [27], electron-rich vinyl ethers [28], and allylic alcohols [29] is accessible through Heck reactions. Allylic alcohols yield C-C-saturated carbonyl compounds (aldehydes) for mechanistic reasons (y9-H elimination), as exemplified in eq. (6). 

These compounds are able to fragment by thermally induced a-elimination into an alkylmetal halide and a trihalomethylcarbene (or dihalomethylcarbene). In the presence of an acyclic or cyclic alkene, cyclopropanation by the carbene can occur. Some substituted cyclopropanes so formed are not stable to the rather forcing conditions. 

The other approach to 2-thioxo-l,2-thiaphospholanes 108 and 110 is based on the direct reaction of an unsaturated hydrocarbon, phosphorus pentasulfide and a thiophosphoric acid halide under drastic conditions (autoclave, 150-200 °C, 10-18 h) [142, 143], When cyclic alkenes (e.g. cyclohexene) are used as the starting substrates, bicyclic compounds are formed with one of the rings representing 1,2-thiaphos-pholane (Scheme 64). These reaction products are used as antioxidant additives for motor oils, polymers and agrochemicals. 

Simple Authors alkanes Congested alkanes C3 Cycloalkanes (size) C4 C5--C7 C8-C12 Poly- cyclics Con- jugated Alkenes Alkynes alkenes Silanes Thianes Halides Ketones Aromatic Acid deriv. 

The palladium-catalysed Mizoroki-Heck reaction is the most efficient route for the vinyla-tion of aryl/vinyl halides or triflates. This reaction, in which a C—C bond is formed, proceeds in the presence of a base (Scheme 1.1) [1, 2], Nonconjugated alkenes are formed in reactions involving cyclic alkenes (Scheme 1.2) [le, 2a,c,e,g] or in intramolecular reactions (Scheme 1.3) [2b,d-g] with creation of stereogenic centres. Asymmetric Mizoroki-Heck reactions may be performed in the presence of a chiral ligand [2], The Mizoroki-Heck reaction has been intensively developed from a synthetic and mechanistic point of view, as expressed by the impressive number of reviews and book chapters [1,2]. 

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