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Amines, alkenyl, reaction with

In the reaction of aryl and alkenyl halides with 1,3-pentadiene (248), amine and alcohol capture the 7r-allylpalladium intermediate to form 249. In the reactions of o-iodoaniline (250) and o-iodobenzyl alcohol (253) with 1,3-dienes, the amine and benzyl alcohol capture the Tr-allylpalladium intermediates 251 and 254 to give 252 and 255[173-175]. The reaction of o-iodoaniline (250) with 1,4-pen tadiene (256) affords the cyclized product 260 via arylpalladiuni formation, addition to the diene 256 to form 257. palladium migration (elimination of Pd—H and readdition to give 258) to form the Tr-allylpalladium 259, and intramolecular displacement of Tr-allylpalladium with the amine to form 260[176], o-Iodophenol reacts similarly. [Pg.164]

Reduction of iV-(3-bromopropyl) imines gives a bromo-amine in situ, which cyclizes to the aziridine. Five-membered ring amines (pyrrolidines) can be prepared from alkenyl amines via treatment with N-chlorosuccinimide (NCS) and then BusSnH. " Internal addition of amine to allylic acetates, catalyzed by Pd(PPh3)4, leads to cyclic products via a Sn2 reaction. Acyclic amines can be prepared by a closely related reaction using palladium catalysts. Three-membered cyclic amines (aziridines)... [Pg.500]

The action of chloroamine and bromoamine on organometallic reagents has been reviewed102 and a comprehensive review of electrophilic aminations of carbanions has appeared103. Alkyl, alkenyl and aryllithium compounds are converted into tertiary amines 84 by reaction with the mesityl compounds 83 (R2 = Me or Et Ar = 2,4, 6-MesCeHj)104. [Pg.552]

Undecylenic acid has also been shown to react with the surface preferentially at the alkene end, leaving the terminal carboxylic acid group free for further reaction [53], This result was somewhat unexpected as the Si-H sites are considered to be somewhat acidic and the oxophilic nature of silicon should thermodynamically favor reaction with the hydroxyl group of the acid. The preferential reactivity with the alkenyl end is consistent with a free radical, rather than a nucleophilic mechanism. The acid function can be activated with N-hydroxy succinimide (NHS) to facilitate coupling with amine tagged molecules. Schematically,... [Pg.301]

As described above (Section 5.2), the Stephens-Castro reaction of alkynylcopper with aryl and vinyl halides in boiling pyridine is a useful route to aryl and vinyl acetylenes. Direct cross-coupling of organic halides, such as sp halides, with terminal alkynes is a more convenient procedure. Such a reaction is not so easy, but it can be done using a Pd-complex catalyst [41]. Especially facile Pd-catalyzed cross-coupling of aryl and alkenyl halides with terminal alkynes proceeds smoothly under mild conditions in the presence of a cocatalyst of cuprous iodide in amine solvents [Eq. (28)] [42]. This methodology is now used widely for the constiuction of conjugated arylalkyne or enyne systems [43], as described below. It is attractive from a synthetic point of view because mild reaction conditions and simplicity of the procedure are associated with recent developments in modem acetylene chemistry [44]. [Pg.388]

A(-(Arylthiomethyl)amines, which are easily prepared and reportedly have better shelf stability than the corresponding )V-(alkoxymethyl)amines, have also been utilized to prepare tertiary amines. Alkenyl cuprate addition to )V,A -diethylphenylthiomethylamine produces allylic amines in high yield (entry 1, Table 6). Both alkenyl groups of the cuprate react. 5-(Dialkylaminomethyl) dithiocarbamates (entry 2, Table 6), sulfonates (entry 3, Table 6) and amides also generate iminium salts in situ. Of a variety of amides examined, imides such as dialkylaminomethyl-succinimides (entry 4, Table 6) and -phthali-mides provide the best overall yields. Organolithium reagents are rarely utilized in aminomethylation reactions. However, )V-chloromethylamines condense readily with lithiated anisole derivatives (entry S, Table 6). ... [Pg.370]


See other pages where Amines, alkenyl, reaction with is mentioned: [Pg.168]    [Pg.483]    [Pg.68]    [Pg.565]    [Pg.293]    [Pg.555]    [Pg.91]    [Pg.282]    [Pg.408]    [Pg.202]    [Pg.72]    [Pg.440]    [Pg.128]    [Pg.137]    [Pg.5]    [Pg.58]    [Pg.58]    [Pg.282]    [Pg.203]    [Pg.54]    [Pg.539]    [Pg.575]    [Pg.125]    [Pg.431]    [Pg.84]    [Pg.471]    [Pg.5281]    [Pg.345]   


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Amination alkenyl

Reaction with amines

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