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Olefinic adds amines

The procedure is illustrative of a general method of ethylating amines, wherein one reacts the amine with ethylene using an alkali-metal salt of the amine as catalyst.2 Di- -butylamine and -hexylamine have been thus ethylated at 130-160°, aniline, o-toluidine, and N-methylaniline at 240-275°. In general, higher olefins add to amines only sluggishly.2... [Pg.47]

Michael condensations are catalyzed by alkaU alkoxides, tertiary amines, and quaternary bases and salts. Active methylene compounds and aUphatic nitro compounds add to form P-substituted propionates. These addition reactions are frequendy reversible at high temperatures. Exceptions are the tertiary nitro adducts which are converted to olefins at elevated temperatures (24). [Pg.151]

A -Halogenated compounds such as iV-chlorotnfluoroacetamide, A -chloro-imidosulfuryl fluonde and N N dichlorotnfluoromethylamine add across C=C bonds to form saturated amides [14] tmidosulfury I fluorides [15] and amines [16], respectively Allylic halogenation also occurs with the use of A-bromo- or A-chIo roperfluoroamides The primary amine A,A-dichlorotrifluororaethylamine selectively affords 11 or 2 1 adducts with either tetrafluoroethylene or chlorotrifluoroethylene [16] (equation 7) The reaction mechanism is believed to involve thermal free radicals, with control achieved principally by reaction temperature The 1 1 adduct is formed even in the presence of a large excess of olefin... [Pg.744]

Allyl p-tolyl sulphoxide 535 reacts with sodium methoxide in methanol by initial prototropic isomerization and subsequent addition of methanol to give 536 (equation 333). Protic solvents are photochemically incorporated by the open chain olefinic bond of trans methyl )S-styryl sulphoxide 537 in a Markovnikov regiospecificity (equation 334). Mercaptanes and thiophenols add to vinyl sulphoxides in a similar manner (compare also Reference 604 and Section IV.B.3) to give fi-alkylthio(arylthio)ethyl sulphoxides 538 (equation 335). Addition of deuteriated thio-phenol (PhSD) to optically active p-tolyl vinyl sulphoxide is accompanied by a low asymmetric a-induction not exceeding 10% (equation 336) . Addition of amines to vinyl sulphoxides proceeds in the same way giving )S-aminoethyl sulphoxides in good to quantitative yields depending on the substituents at the vinyl moiety When optically active p-tolyl vinyl sulphoxides are used in this reaction, diastereoisomeric mixtures are always formed and asymmetric induction at the p- and a-carbon atoms is 80 20 (R = H, R = Me) and 1.8 1 (R = Me, R = H), respectively (equation 337) ... [Pg.351]

Several examples of the photoaddition of amines and amine derivatives to olefins have been reported/921 Butylamine adds to 1-octene upon ultraviolet irradiation to produce 4-aminoalkane ... [Pg.270]

IV-Nitrosoamines undergo addition to olefins upon photolysis in the presence of acid to produce a-r-aminonitrosoalkanes in which the amine moiety adds to the less substituted carbon of the double bond<96) ... [Pg.270]

Chen and co-workers utilized the chiral bifunctional catalysts to directly access vinylogous carbon-carbon bonds via the asymmetric Michael addition of a,a-dicy-ano-olefms to nitro-olefms [102]. The scope of the reaction was explored with a variety of substituted a,a-dicyano-olefins and P-substituted nitro-olefms (Scheme 50). The authors propose the catalysf s tertiary amine functionality depro-tonates the cyano-olefm, activating the nucleophile to add to the -face of the pre-coordinated nitro-olefm. [Pg.179]

Although the intramolecular aminocarbonylation described above is an extension of the standard amide-forming reaction, a different type of intramolecular aminocarbonylation has been studied, wherein the amine moiety adds across the olefin moiety activated by a Pd catalyst to generate /3-aminoalkyl-Pd species, followed by CO insertion and alcoholysis, forming a lactone or an ester. ... [Pg.536]

Additions to Aromatic Hydrocarbons. A variety of photochemical additions to aromatic hydrocarbons have been reported. Benzene and its derivatives add to maleic anhydride74-76 as well as to simple olefins,77-80 isoprene,81 acetylene derivatives,79,82 and alcohols.83 The mechanism of the maleic anhydride-benzene reaction is discussed in Section IV. A.4. Naphthalene forms a photoadduct with dimethyl acetylenedicarboxylate62 and with acrylonitrile8211 while anthracene behaves similarly with maleic anhydride84 and with 1,2-benzanthracene.85 The photoaddition of several aromatic amines to anthracene has been reported to proceed via a charge transfer complex86,87 in fact, the majority of these addition reactions may proceed in this manner. [Pg.257]

Alkyl amines add photochemically to olefins a condensation occurs between the a-carbon atom of the amine and the terminal carbon atom of 1-olefins by what is probably a free-radical, chain reaction.291 Internally illumination of solutions, containing piperidine and octene-1, with a mercury discharge tube led to the formation of 2-n-oetylpiperidine (CXLV). [Pg.101]

Huisgen has stated that the driving force behind the 1,3-dipolar addition is stronger the more the loss of T-bond energy in the reactants is overcompensated by the energy of the two new bond energy is O-N < N-N < C-N, azides do not add at all to aldehydes and ketones and add with more difficulty to nitriles than to olefins. Phenyl azide, for instance, adds preferentially to the C-C double bond of acrylonitrile.194 103 This is also the reason why the condensation products of aldehydes and primary amines, which essentially exist in the Schiff-base structure 46a, react in the tautomeric enamine form 46b.2 ... [Pg.17]

The activity of homogeneous catalysts also has been demonstrated Wilkm son s catalyst tris(triphenylphosphine) rhodium chloride induces petfluoroalkyl iodides to add to olefins at 80 °C [10] (equation 10) Tetrakis(tnphenylphosphme)-palladtum promotes the addition to both alkenes and alkynes in hexane [11] Amines and amine salts induce addition at 120-140 °C [12] (equation 11)... [Pg.748]

The reaction conditions applied are usually heating the amine with a slight excess of aldehyde and a considerable excess of 20-30% hydrochloric acid at 100 °C for a few hours, but much milder ("physiological ) conditions can be used with good success. Diols, olefinic double bonds, enol ethers, and glycosidic bonds survive a Pictet-Spengler reaction very well, since phenol and indole systems are much more reactive than any of these add sensitive functional groups (W.M. Whaley, 1951 J.E.D. Barton, 1965 A.R. Battersby, 1969). [Pg.292]

Some success has been achieved using all of the above olefinic compounds in reactions with vinylic halides and amines to add the number of carbons indicated, selectively to form one isomeric product or one which is separated easily from a mixture that may have been formed. Numerous other similar reagents may be imagined, but either they have not been tried or successful reactions were not found. [Pg.217]

Although the anodic generation of a cation in a-position to nigrogen in aliphatic amines is not difficult, this type of reaction is not always useful to the synthesis of alkaloidal compounds, since the cation is not stable and a simple dealkylation is the usual follow-up reaction. N-monomethyl and N,N-dimethylanilines are, however, useful starting materials for the synthesis of the skeleton of tetrahydroquinoline. The anodic methoxylation of N,N-dimethylaniline 20 takes place at the methyl group, and an iminium ion intermediate 22 is easily generated by treatment of the methoxylat-ed product 21 with Lewis add. This intermediate can be trapped in situ with a variety of nucleophiles such as electron-rich olefins yielding tetrahydroquinolines 23 16). [Pg.138]

All these reactions proceed most likely by initial activation of the iron(0) species by a ligand exchange with the activating additives, such as amines, benzonitrile or DMF (Fig. 7). Thus generated mononuclear iron complexes bearing a labile ligand are activated to form coordinatively unsaturated iron complexes 37A. These species reduce the polyhalo compounds to radicals 38A, which add to olefins 30 or 33. [Pg.207]

Diorganozincs can also be prepared by a nickel-catalyzed hydrozincation. The reaction of Et2Zn with Ni(acac)2 may produce a nickel hydride that adds to an alkene leading after transmetallation with Et2Zn to a diakylzinc (Scheme 9). This reaction proceeds in the absence of solvent and at temperatures of 50-60 °C. A number of functionalized olefins like allylic alcohols or amines can be directly used. This method is especially well suited for the preparation of functionalized diorganozincs for the asymmetric addition to aldehydes (Equation (45)).108,50... [Pg.95]


See other pages where Olefinic adds amines is mentioned: [Pg.214]    [Pg.243]    [Pg.66]    [Pg.186]    [Pg.542]    [Pg.464]    [Pg.269]    [Pg.454]    [Pg.456]    [Pg.164]    [Pg.136]    [Pg.351]    [Pg.218]    [Pg.740]    [Pg.220]    [Pg.439]    [Pg.768]    [Pg.768]    [Pg.783]    [Pg.800]    [Pg.128]    [Pg.344]    [Pg.359]    [Pg.87]    [Pg.64]    [Pg.76]    [Pg.139]   
See also in sourсe #XX -- [ Pg.92 , Pg.188 ]




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