Telomerizations of olefines

The trichloromethyl group can be reduced to either the dichloro- or the monochloromethyl group by proper choice of the SSE 49 s With ammonium nitrate the dichloro compounds are formed in 64—94% yield, while with tetra-metliylammonium chloride as supporting electrolyte the monochloro derivatives are obtained in 63 to 95% yield. As trichloromethyl compounds are readily available by telomerization of olefins with CC14) this reduction opens a simple route to a, co-bifunctional aliphatic compounds. 

In addition to the applications reported in detail above, a number of other transition metal-catalyzed reactions in ionic liquids have been carried out with some success in recent years, illustrating the broad versatility of the methodology. Butadiene telomerization [34], olefin metathesis [110], carbonylation [111], allylic alkylation [112] and substitution [113], and Trost-Tsuji-coupling [114] are other examples of high value for synthetic chemists. 

YoshimuraN (2000) Telomerization (hydrodimeiization) of olefins. In Cornils B, Herrmann WA (eds) Applied homogeneous catalysis with organometallic compounds A comprehensive handbook. Special Workbench ed. Wiley-VCH, Weinheim. 

Linear oligomerization and telomerization of butadiene take place with nickel complexes in the presence of a proton source (7). In addition, cooligomerization of butadiene with functionalized olefins such as methacrylate is catalyzed by nickel complexes [Eq. (4)] (12, 13) ... 

The first reactions of fluorinated olefins in C02 reported by DeSimone et al. involved the free-radical telomerization of 1,1 -difluoroethylene29 and tetrafluor-oethylene.30 This work demonstrated the feasibility of carrying out free-radical reactions of highly electrophilic species in solvents other than expensive fluorocarbons and environmentally detrimental chlorofluorocarbons. The work has since been more broadly applied to the synthesis of tetrafluoroethylene-based, nonaqueous grades of fluoropolymers,31,32 such as poly(tetrafluoroethylene-co-peduoropropylvinyl ether) (Scheme 2). These reactions were typically carried out at between 20 and 40% solids in C02 at initial pressures of between 100 and 150 bars, and 30-35°C (Table 10.1). 

Telomerization is the reaction of olefins having conjugated double bonds (conjugated dienes) in the presence of a nucleophile (telogen). The main... 

The telomerization of butadiene by means of water in ILs was described by Dullius et Rottger et al. report a process for the telomerization of acyclic olefins having at least two conjugated double bonds, or their mixtures, using a palladium-carbene complex as catalyst in an IL solvent. The nucleophiles included water, alcohols, phenols, polyols, carboxylic acids, ammonia and primary and secondary amines. The acycylic olefins could be either 1,3-butadiene or isoprene. 

J.L. Herisson and Y. Chauvin, Catalysis of olefin transformations by tungsten complexes. II telomerization of cyclic olefins in the presence of acyclic olefins, Makromol. Chem., 141 161-176,1971. 

Although various transition-metal complexes have reportedly been active catalysts for the migration of inner double bonds to terminal ones in functionalized allylic systems (Eq. 3.2) [5], prochiral allylic compounds with a multisubstituted olefin (Rl, R2 H in eq 2) are not always susceptible to catalysis or they show only a low reactivity [Id]. Choosing allylamines 1 and 2 as the substrates for enantioselective isomerization has its merits (1) optically pure citronellal, which is an important starting material for optically active terpenoids such as (-)-menthol, cannot be obtained directly from natural sources [6], and (2) both ( )-allylamine 1 and (Z)-allylamine 2 can be prepared in reasonable yields from myrcene or isoprene, respectively, The ( )-allylamine 1 is obtained from the reaction of myrcene and diethylamine in the presence of lithium diethylamide under Ar in an almost quantitative yield (Eq. 3.3) [7], The (Z)-allylamine 2 can also be prepared with high selectivity (-90%) by Li-catalyzed telomerization of isoprene using diethylamine as a telomer (Eq. 3.4) [8], Thus, natural or petroleum resources can be selected. 

Jackstell R, Andreu MG, Frisch A, Selvakumar K, Zapf A, Klein H, Spannenberg A, Rottger D, Briel O, Karch R, Beller M (2002) A highly efficient catalyst for the telomerization of 1,3-dienes with alcohols first synthesis of a monocarbenepalladium(0)-olefin complex. Angew Chem Int Ed 41 986-989... 

Several catalytic systems have been investigated for hydroamination of unsaturated bonds [16]. Takahashi et al. reported the telomerization of 1,3-dienes in the presence of an amine leading to octadienylamine or allylic amines when palladium catalysts are used in association with monodentate or bidentate phosphine ligands, respectively [17]. Dieck et al. demonstrated the beneficial effect of addition of an amine hydroiodic salt in the hydroamination reaction of 1,3-dienes in which the allylic amines are produced via an intermediate Jt-allyl palladium complex [18]. Coulson reported the Pd-catalyzed addition of amines to allenes where dimerization is incorporated [4]. This reaction presumably proceeds via a cyclic palladium intermediate in which the Pd activates the olefinic bond for nucleophilic attack the reactions are therefore different from pronucleophilic additions. 

The telomerization of fluorinated olefines with alcohols as telogens leads to co-hydroperfluoro alcohols ... 

J.-L. Herisson, and Y. Chauvin, Catalysis of Olefin Transformations by Tungsten Complexes. Telomerization of Cyclic Olefins in the Presence of Acyclic Olefins, Makro-mol. Chem. 141, 161-167 (1971). 

A novel method of stereospecific olefin formation was used by Tsuji for the elaboration of intermediate 18 (Scheme 1.5). ° Palladium(II)-mediated telomerization of butadiene in nitroethane gave a 56% isolated yield of the ( )-nitro olefin 18. One rationale for the high stereospecificity in the bondforming steps of this reaction arises from an examination of the mechanism. The addition of Pd to butadiene causes initial formation of a dimeric bis ir-allyl palladium species. The bis TT-allyl species 18a and the o-allyl species 18b (Eq. 

Tsuji has completed three syntheses of zearalenone (119), all by quite similar routes. The first, shown in Scheme 1.28, began with acetate 59b, the minor product from the telomerization of butadiene in acetic acid. Cleavage to the alcohol and gas-phase dehydrogenation led to enone 141. Chain extension to 142 was accomplished in 70% yield by way of Michael addition of diethyl malonate to enone 141. Decarboalkoxylation and protection of the ketone then gave 143 (63%). Conversion of the ester to the primary tosylate 144 was achieved by conventional methods in 62% yield. A Wacker oxidation of the terminal olefin followed by reduction and exchange of the tosylate for an iodide then provided the aliphatic segment 145 in 64% yield. 

Oligomerizations, polymerizations and telomerizations are covered in other parts of this section, since C-C/C-C bond forming additions (dicarborations) are involved. Metal-mediated hydroalkylations of olefins with CH acidic compounds and hydroarylations with formal addition of aromatic C—H bonds to olefins are also known2, however, only a few examples of stereoselective applications have been reported (Section 1.5.8.2.6.). 

Table VII. Telomerization of Ethylene with Olefinic Telogens ...

Telomerization of Conjugated Diolefins with Aromatics and Olefins Using Chelated Organosodium Catalysts... 

Telomerization of butadiene and isoprene with aromatics and olefins proceeds rapidly at 0°-100°C using organosodium catalysts in combination with aliphatic tertiary chelating polyamines containing two to six nitrogens. The products range from monoadduct up to tacky semisolids. 

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