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Amines hydroxy, rearrangement

Despite many attempts it has not been possible to oxidize 2-substituted 1,2,3-triazoles 382 to the corresponding 1-oxides 326. Peracetic acid, 3-chloroperbenzoic acid, dichloropermaleic acid, trifluoroperacetic acid, peroxydisulfuric acid, and f-pentyl hydrogen peroxide in the presence of molybdenum pentachloride all failed to oxidize 382 (1981JCS(P1)503). Alkylation of 1-hydroxytriazoles 443 invariantly produced the isomeric 3-substituted 1,2,3-triazole 1-oxides 448 (see Scheme 132). However, the 2-substituted 1,2,3-triazole 1-oxides 326 can be prepared by oxidative cyclization of 2-hydroxyiminohydrazones (1,2-hydrazonooximes, a-hydrazonooximes) 345 or by cyclization of azoxyoximes 169. Additional methods of more limited scope are reaction of nitroisoxazoles 353 with aryl-diazonium ion and base, and reaction of nitroimidazoles 355 with hydroxy-amine- or amine-induced rearrangement of nitro-substituted furoxanes 357. [Pg.61]

A tandem aza-Wittig/heterocumulene-mediated annulation route was developed for the efficient production of 6,7,8,9-tetrahydro-benzothieno[2,3-r/]-l,2,4-triazolo[l,5-a]pyrimidin-10(3F/)-ones <05S1601>, and an amine oxide rearrangement was key to the regioselective preparation of pyrrolo[2,3-J]pyrimidines <0581164>. Hexahydro-2-phenacylidene-pyrimidines gave -lactam fused 8-aroyl-2,3,4,5-tetrahydro-7-hydroxy-6//-pyrrolo[l,2-a]py-rimidine-6-ones when treated with (COCl), in the presence of NaH <05IJH87>, and methyl... [Pg.363]

Certain 2-amino ketones undergo rearrangement on thermolysis to produce new 2-amino ketones. The reaction proceeds by an initial 1,2-shift to yield a hydroxyimine, followed by a second 1,2-shift to the observed product (Scheme 23). The amine must be primary or secondary and attached to a tertiary center. As would be expected, 2-hydroxyimines rearrange to 2-amino ketones (equation 40). Similarly, 2-hydroxy ketones when heated with amines form rearranged 2-amino ketones via 2-hydroxyimines (equation 41). This reaction has been applied in the synthesis of a D-ring homosteroid (equation 42). ... [Pg.790]

The CR NR group can be introduced into ammonia, amines, hydroxy compounds, carboxamides, and sulfonamides to form amidines, imido-esters, etc., via imidosulfonates, obtained by the Beckmann rearrangement of oxime sulfonates.—B Benzophenone oxime benzene sulfonate and aniline warmed in benzene, and, after the exothermic reaction has ceased, further refluxed for 15-30 min. —>- N,N -diphenylbenzamidine. Y 92.5%. (F. e. s. P. Oxley and W. F. Short, Soc. 1948,1514.)... [Pg.355]

If a bromomethyl- or vinyl-substituted cyclopropane carbon atom bears a hydroxy group, the homoallyiic rearrangement leads preferentially to cyclobutanone derivatives (J. Sa-laun, 1974). Addition of amines to cydopropanone (N. J. Turro, 1966) yields S-lactams after successive treatment with tert-butyl hypochlorite and silver(I) salts (H.H. Wasserman, 1975). For intramolecular cyclopropane formation see section 1.16. [Pg.77]

The formation of tluorinated Q -hydroxy-jS-imino esters (180) by treatment of fluorinated imino ethers (179) with lithium 2,2,6,6-tetramethylpiperidide has been reported. A possible explanation for this interesting intramolecular rearrangement is proposed in Scheme 64. Acyclic imides derived from primary benzylic amines and amino acid esters have been found to undergo a novel nitrogen to carbon acyl migration via a base-generated carbanion to yield the corresponding a-amino... [Pg.546]

Activated A-alkyl-O-acylhydroxamic acid derivatives 75 undergo base catalysed rearrangement to give 2-acyloxyamides 76 in good to excellent yields (50-100%) (equation 26). These precursors of 2-hydroxy amides (77) are good intermediates to prepare ethanol-amines, oxindoles and oxazolidinediones. [Pg.360]

The resulting /3-alkythiohydroperoxides can be isolated, but they normally rearrange to /3-hydroxy sufoxides, or in the presence of amines they are reduced to alcohols with concomitant oxidation of two further molecules of mercaptan to disulfide (16). [Pg.180]


See other pages where Amines hydroxy, rearrangement is mentioned: [Pg.363]    [Pg.160]    [Pg.726]    [Pg.235]    [Pg.91]    [Pg.470]    [Pg.713]    [Pg.1411]    [Pg.70]    [Pg.351]    [Pg.355]    [Pg.537]    [Pg.37]    [Pg.1266]    [Pg.435]    [Pg.549]    [Pg.176]    [Pg.48]    [Pg.973]    [Pg.64]    [Pg.57]    [Pg.104]    [Pg.516]    [Pg.973]    [Pg.540]    [Pg.389]    [Pg.516]    [Pg.516]    [Pg.636]    [Pg.726]    [Pg.77]    [Pg.439]    [Pg.146]    [Pg.146]    [Pg.92]    [Pg.501]    [Pg.596]    [Pg.187]   
See also in sourсe #XX -- [ Pg.337 , Pg.338 ]




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Amination hydroxy

Amines rearrangements

Hydroxy amines

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