Halides allylation

The original synthetic processes using organonickel compounds involved the coupling of halides. Allylic halides react with nickel carbonyl, Ni(CO)4, to give re-ally I... 

The concept of CPTC has been applied in a large number of catalytic reactions such as reduction of allyl chlorides with HCOONa, carbonylation of aryl and allyl halides, allylation of aldehydes, cyanation of aryl halides etc.214 For example, Okano et a/.215 reduced l-chloro-2-nonene to afford 1-nonene and... 

Organic halide Allylic alcohol Catalyst Reaction conditions Products % yield)... 

Seyferth reagents are ideal for the dihalocyclopropanation of deactivated or base sensitive substrates such as allyl halides, allyl isocyanates, polychloroalkenes, a, 3-unsaturated ketones, esters, nitriles and sulfones.19... 

In summary, it can be said that the Y-substituted allylphenols can be prepared by Oalkylation of the sodium salt of the phenol in benzene, and —they usually cannot be prepared by the Claisen rearrangement. The condensation of free phenols with allylic halides, allylic alcohols, and dienes may give allylphenols, but frequently yields other products. - 94... 

The method is an extension of the well-known Grignard synthesis in ethers to the use of nonsolvating media, and is a development of procedures previously reported.2-6 A version of it has been employed with straight-chain primary alkyl chlorides, bromides, and iodides from C2 to Cu,5-7 and in solvents (or an excess of the halide) which permit reaction temperatures above 120°, with simple aryl halides such as chlorobenzene and 1-chloro-naphthalene. Branched-chain primary, secondary, and tertiary alkyl halides, allyl, vinyl, and benzyl halides either fail to react or give extensive side reactions. Better results are reported to be obtained in such cases with the use of catalytic quantities of a mixture of an alkoxide and an ether such as diethyl ether or tetrahydrofuran in a hydrocarbon medium, but the products are not, of course, completely unsolvated.4... 

OxazoIones are alkylated at position 4 by alkyl halides, allyl halides and electrophilic alkynes, such as methyl propiolate (equation 36). In contrast, 2-phenyloxazolones react with methyl vinyl ketone at both C(4) and C(2) to yield a mixture of Michael adducts (equation 37). If the phenyl substituent is replaced by the bulky 2,4,6-trimethylphenyl group the addition is directed exclusively to C(4) (81CB2580). Alkylation of 5(4//)-oxazolones is a key step in the synthesis of ketones from a-amino acids (Scheme 16). The outcome of this sequence is the union of the electrophilic fragment R3 with the group R2CO the amino acid thus functions as the equivalent of an acyl anion (78AG(E)450). 

Polymerization was carried out in benzene in the presence of bis-(7r-allylnickel halides). The latter were prepared from nickel carbonyl and allyl halide (allyl bromide, crotyl chloride, bromide, or iodide etc.). The results of the polymerization runs are reported in Table I. The data indicate that all of the bis(7r-allylnickel halides) initiate by themselves the stereospecific butadiene polymerization yielding a polymer with 97-98% 1,4-units. The cis-l,4/trans-l,4 ratio depends on the halide in the dimeric r-allylnickel halide but not on the nature of allylic ligand. The case of bis(7r-crotylnickel halides) shows the effect of halide on microstructure, for whereas (C4H7NiCl)2 initiates cis- 1,4-polybutadiene formation, trans-1,4 polymers are produced by (C4H7NiI)2. The reactivity increase in the series Cl < Br < I. 

CuCN halide allylic halide or tosylate JACS 109 8056 (1987) JOC 52 4418 (1987)... 

H, alkyl, vinyl, aryl, heteroaryl R X = aryl/vinyl hallde/trlflate, alkyl halide, allyl ester... 

Reduction of aikyl halides. Allylic and benzylic chlorides and bromides are reduced by the reagent almost instantaneously at 25° (S 2 displacement). Simple primary halides are completely reduced in 2 min. Even neopentyl bromide is reduced to neopentane (96% yield) in 3 hr. under reflux. Secondary cycloalkyl bromides are reduced at 25° in 24 hr. Even CAro-2-bromonorbomane (I) can be reduced quantitatively. The... 

HALIDES, ALLYLIC alkanes + halo-succinimides 14-03 from aldehydes or ketones 16-24... 

Tellurium-containing heterocyclic compounds also react with methyl halides, ethyl halides, allyl halides, benzyl bromide, and benzoylmethyl bromides, with or without a solvent, to produce telluronium halides. Tetrahydrotellurophene, l-methyltetrahydrotellurophene, 2,7-dihydrobenzo[c] tellurophene, 1-benzotellurophene 2-oxo-2,3-dihydro-l-benzo-tellurophene, dibenzotellurophene , 1,4-oxatellurane l,4-thiatellurane °, 3,4-dihydro-l/f-2-benzotellurin, and 4-oxo-2,3-dihydro-47/-l-benzotellurin" reacted to produce telluronium halides. 

Allylic Systems. Allylic Halides. Allylic halides also undergo homolytic carbon-halogen cleavage by pentacyanocobaltate(II) to form equimolar quantities of halo- and allylcobalt complexes (21, 22, 23). It is assumed that this reaction involves generation of the allylic radical (Reaction 19), which then reacts with pentacyanocobaltate(II) (Reaction 20). 

A useful method of preparing 1-alkenes involves reaction of Grignard reagents with the unusually reactive halide, allyl bromide ... 

Vinylcopper reagents react with a wide variety of electrophilic reagents such as halogens, alkyl halides, allylic halides, acid chlorides, epoxides, a,(3-unsaturated ketones, and a,p-acetylenic esters with complete retention of the double bond stereochemistry. To enhance the reactivity of vinylcopper intermediates toward carbon electrophiles, the coupling is often carried out in the presence of activators such as HMPT, DMPU, and/or P(OEt)3 (triethylphosphite). Some representative examples of stereospecific... 

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