Quinolines formates

Quinoid-type chromophoric structures, reactions of, 21 36-37 Quinoline (QI), 12 723, 725-726 soluble dyes, 7 373t Quinoline-4-carboxylic acids, 21 190 Quinoline derivatives, 21 196-214 Quinoline-derived drugs, 21 197-198t Quinoline dyes, 21 196 Quinoline, formation of, 21 109. See also Quinolines... 

For the formation of the 4-ethynylquinoline complexes a mechanism was proposed involving nucleophilic attack of the terminal carbon of the butatrienylidene ligand at the imine carbon, followed by C—C bond formation between the ortho carbon of the N-aryl group and C3 of the butatrienylidene ligand. Deprotonation finally affords 4-ethynylquinoline complexes (Scheme 3.27). Some preference was observed for quinoline formation with the more electron-rich metal centers, whereas... 

Another case of quinoline formation is the condensation of benzoyl acetone and aniline, resulting in y-plieny l-qnirialdine ... 

Reaction of lithiated 3-enaminophosphonj tes of aniline and isocyanates with subsequent cyclization of the resulting amides with triphenylphosphine/triethylamine leads to the 3-phosphonyl-4-aminoquinolines (Equation 92) <1999T5947>. Aniline reaction with /3-diketones < 1999H(51 )2171 > and ethoxymethylenemalonates <1999JFC(94)7> also leads to quinoline formation. The Vilsmeier reaction conditions can also be applied to the synthesis of quinolines with the use of a-oxoketene /V -anilinoacetals (Equation 93) <2003JOC3966>. 

Oxidative methylamination of 2-, 3-, 4-, 5-, 6-, 7-, and 8-nitroquinolines at —7 °C leads, as could be expected, to similar results as obtained in the oxidative amination (93LAC823). In general, the methylamination differs from the oxidative amination in several aspects (a) the reaction occurs faster than the amination, due to the higher temperature at which the reaction is carried out, (b) gives higher yields, (c) the site specificity is less than observed in the amination, as it appears by the sometimes occurring formation of mixtures of (methylamino)nitroquinolines, and even in the case of 5-nitro-quinoline formation of bis(methylamino)-5-nitroquinolines (Table III). 

The quinoline formation from 2,4-dinitrophenyl oximes suggested to us the possibility of generating radical intermediates and prompted us to study the synthesis of cyclic imines by iminyl radical addition to an internal olefinic moiety as shown in Scheme 44. 

N-Substituted acetanilides (69), the original substrates studied by Vilsmeier (see Scheme 1), are highly reactive compounds for quinoline formation. Thus, quinolinium salts (70) derive from the action of phosgene,55 while 2-quino-lones (71) are readily formed by Vilsmeier formylation of the same sub-strates." b 7 The formylation of IV-phenylacetanilides (69 R1 = Ph) was initially misinterpreted,58 but has now been shown to be a highly efficient route to l-phenyl-2-quinolones.57... 

The biosynthetic pathway which is indicated by the above results is illustrated in Scheme 11 norlaudanosoline (70) had previously been shown to be a morphine (71) precursor. The implication of a keto-acid rather than an aldehyde in benzyliso-quinoline formation accords with observations on the biosynthesis of simpler isoquinolines and stands in contrast with the utilization of an aldehyde, sec-ologanin, in a similar reaction in the biosynthesis of terpenoid indole alkaloids. ... 

Quinoline formation by annelation of a benzene ring onto a pyridine ring is a less commonly adopted approach but this possibility has been realised by a reaction sequence starting from 2-bromomethyl-3-phenylsulphonylmethylpyridine (77) (Scheme 18). 97... 

The required aldol condensation, whether base- or acid-catalysed, exerts regioselectivity in the case of unsymmetrical ketones. For instance, the quinoline formation from methyl ethyl ketone and 2-benzoylaniline 66 occurs by base catalysis via the enolate giving the 2-ethyl-4-phenylquinoline 67. However, under acid catalysis via the enol, it affords 2,3-dimethyl-4-phenylquinoline 68 ... 

The spiro quinoline formation was applied to a large-membered ring. The substrate 39,bearing a 15-membered ring cyclic olefin and a terminal acetylene was cyclized under the previously described conditions to give the olefin migration product 40 in a moderate yield (53%) but good enantioselectivity (86% ee) (Scheme 29). 

In addition, Schiff bases can also be applied as intermediates of quinoline formation. Thus, Schiff bases derived from 2-(trifluoromethyl) aniline and a methyl naphthone, mediated by lithium 2-(dimethylamino)-ethylamide, were used to furnish a series of substituted 2-(2-naphthyl)quinolines designed to target DNA. ... 

Substituted quinohnes 22 had been synthesized via molecular iodine-catalyzed one-pot domino reaction of imines with enolizable aldehyde by Yan-Guang et al. [51] (Scheme 10.17). They examined different solvents but benzene gave the best result and there was no product formation without using iodine. Different aniline and enolizable aldehydes were tested to afford the corresponding products but with enolizable acetophenone, instead of the aliphatic aldehydes, expected quinoline formation did not occur. 

Benzol/] quinolines formation of, 150, 162 metal catalysts, action on, 189, 196 Benzol/i]quinoline, metal catalysts, action on, 189, 196 Benzoselenazole, 2-amino-, 68 Benzoselenazole-2-thione, 62 Benzoselenazol-2-one, 49 Benzo-1,2,4-thiadiazin-3-ones, methyla -tion of, 259 Benzothiazoles 2-acylamino-, 77... 

Amino)cinnamoyl compounds 79 can be regarded as primary products they may arise from an aldol condensation catalyzed by base, add, or (most frequently) by Lewis acids [173]. Alternatively, quinoline formation may result from primary cross aldol addition, subsequent cydocondensation to an imine(4-hydroxy-3,4-dihydroquinoHne), and aromatization by H2O elimination [174]). 

Table 2.4. Quinoline formation from indoles by carbene addition [42]...

Miscellaneous Reactions. Y(OTf)3 also catalyzes acetal and thioacetal formation, quinoline formation, 5-benzylation of... 

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