Butyl bromide coupling reaction with

A treatment of 2-butyltelluroaniline with an equimolar amount of bromoacetic acid results in spontaneous cyclization of the formed telluronium salt 31 to give 1-butylbenzotellurazinonium bromide 30. That the alkylation occurs at the tellurium and not at the nitrogen atom of 2-butyltelluroaniline has been proved by the isolation of the methyl ester of 31 in 60% yield when the amine was coupled with methyl bromoacetate under the same reaction conditions. Elimination of butyl bromide from 30 readily occurs on heating of its DMF solution leading to 2//-l,4-benzotellurazin-3(4//)-one 32 in 90% yield. 

Polarization also occurs in coupling and disproportionation reactions of Grignard reagents with alkyl halides. The vinyl protons of isobutene produced in the reaction of t-butylmagnesium chloride with t-butyl bromide show A/E polarization as do the methyl protons of isobutane (Ward et al., 1970). Similar results arise in the reaction of diethyl-magnesium with organic halides (Kasukhin et al., 1972). 

Lund and coworkers [131] pioneered the use of aromatic anion radicals as mediators in a study of the catalytic reduction of bromobenzene by the electrogenerated anion radical of chrysene. Other early investigations involved the catalytic reduction of 1-bromo- and 1-chlorobutane by the anion radicals of trans-stilhene and anthracene [132], of 1-chlorohexane and 6-chloro-l-hexene by the naphthalene anion radical [133], and of 1-chlorooctane by the phenanthrene anion radical [134]. Simonet and coworkers [135] pointed out that a catalytically formed alkyl radical can react with an aromatic anion radical to form an alkylated aromatic hydrocarbon. Additional, comparatively recent work has centered on electron transfer between aromatic anion radicals and l,2-dichloro-l,2-diphenylethane [136], on reductive coupling of tert-butyl bromide with azobenzene, quinoxaline, and anthracene [137], and on the reactions of aromatic anion radicals with substituted benzyl chlorides [138], with... 

Figure 6. SEC profiles of PI-6-PS-6-PI triblock copolymer chains end-capped with butyl bromide group (SI44) before and after the coupling reaction in n-hexane, with the self-assembly as well as in THF without the self-assembly.

Radical addition/cross-coupling products 61 were obtained in 60-91% yield when Ni(dppf)Cl2 was applied as a catalyst in reactions of alkyl halides 60 with 2,3-disubstituted dienes 59 and aryl Grignard or arylzinc reagents (Fig. 12). Competition experiments of n-, sec-, and ferf-butyl bromide with 2,3-dimethylbutadiene... 

Most recently, Monteiro et al. have reported that cyclopalladated compounds derived from the ortho-metalation of benzylic tert-butyl thioethers are excellent catalyst precursors for the Suzuki cross-coupling reaction of aryl bromides and chlorides with phenylboronic acid under mild reaction conditions. A broad range of substrates and functional groups are tolerated in this protocol, and high catalytic activity is attained (Eq. (58)) [93]. 

Only perfluoro-tert-butyl copper has been prepared by this method. The compound was isolated in 72% yield from the reaction of m-(tri-fluoromethyl)phenylcopper with perfluoro-fert-butyl bromide in ether-dioxane at 0°C(34). Exchange and cross-coupling reactions occur simultaneously in many reactions between organocopper reagents and various organic halides (69, 97, 174, 217, 220, 266, 297). However, the method is only of limited use as the new reagent [R Cu in Eq. (16)] and its precursor are capable of reacting with both species of halide, RX and R X, present in the mixture. 

Organocopper compounds of stoichiometric ratio RCu do not always react with alkyl bromides (29, 44, 66, 147, 181). Where possible, a reaction may be effected at higher temperatures (128), in a more strongly coordinating solvent (31, 297), or by means of the cuprate species (297). An unsubstantiated coupling reaction between phenylcopper and butyl bromide in an aromatic solvent was mentioned (24), although it is doubtful that an organocopper species was employed (285). 

These palladium and platinum (completely analogous to palladium) complexes were used in the C-C coupling reaction of aryl bromides carrying functional groups in the para position with styrene or n-butyl acrylate at elevated temperatures. 

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