Pyridyl aniline

T3 M 95.6% after 15 days Aniline 4-(2-imino-l-pyridyl)aniline additional metabolites were preliminary assigned but not confirmed [22]... 

Af-EthyI-/V-[3-(4-pyridyl)phenyl]aminomethylenemalonate was prepared in the reaction of /V-ethyl-3-(4-pyridyl)aniline and EMME at 165°C for 0.5 hr (85USP4537735) (Scheme 19). In the reactions of N-alkyl-yV-arylamines (105) and EMME at 120-140°C for 20 min, /V-alkyl-AA-arylaminomethylenemalonates (106) were prepared in 54-81% yields (72HCA1319). 

Af-Ethyl-3-(4-pyridyl)aniline was reacted with isopropylidene ethoxy-methylenemalonate (422) in ethanol at ambient temperature for about 15 hr to give isopropylidene N-ethyl-N-[3-(4-pyridyl)phenyl]aminomethy-lenemalonate in 72% yield [77JAP(K)116460]. 

By this procedure a considerable number of arylpyridines have been prepared. Pyridine derivatives can be prepared also from amines containing the pyridyl group. Thus, the nitrosoacetyl derivative of m-o -pyridyl-aniline can be coupled with benzene to yield 3-a-pyridylbiphenyl (XVI). 

Our group in 2014 developed the first cabonylative [3-I-2-I-1] annulation of Af-pyridyl anilines with internal alkynes and Mo(CO)g toward the facile synthesis of 2-quinolinones, and 19 examples were synthesized [40]. Here, the solid CO source Mo(CO)g was used instead of the CO gas which was highly toxic (Table 15.30). A series of symmetric and asymmetric internal alkynes could... 

Table 15.30 2-Quinolinone synthesis from carbonylative [3-1-2-I-1] annulation of A/-pyridyl anilines with internal alkynes and Mo(CO)gi k...

Table 15.32 Selected examples for the pyridocarbonylatlon of A/-pyridyl anilines to form 11 H-pyrido[2,1 -6]-quinazolin-11 -onel. ...

A special type of ammonio group is represented by 4-( 1 -pyridinium)-pyridine and other azinium analogs. Such products often result from self-quaternization of highly reactive derivatives. A -(4-Pyridyl)-and A -(3-nitro-4-pyridyl)-pyridinium chloride hydrochlorides (121) react with aniline, chloride ion, and water to give 4-substituted pyridines plus pyridine. l-(2-Quinolyl)- and l-(4-quinolyl)-pyridinium salts undergo 2- and 4-substitution, respectively, with amines, anilines, hydroxylamine, phenols, alkoxides, mercaptans, and chloride... 

The residual oil is subjected to distillation under reduced pressure, the fraction boiling in the range of 185°Cto 198°C/4 mm Hg being collected. Purification of the fraction by redistillation under reduced pressure gives 22.5 parts by weight of N-(2-piperidinoethyl)-N-(2-pyridyl-methylj-aniline which boils at 195°C to 196°C/4 mm Hg. Yield 76.3%. 

Another class of new ligands was prepared in quantitative yields by Feringa et al., in 1997, by reaction between a-mercapto acids, aniline and 2-pyridine-carboxaldehyde." These pyridyl-substituted thiazolin-4-one ligands were further involved in the copper-catalysed conjugate addition of ZnEt2 to 2-cyclohexenone,... 

A A -coordi nation was found in the zinc complex of 2,2 -dipyridyl diselenide, [ZnLCl2].214 The tridentate ligand 6-(2-aminophenyl)-2,2 -bipyridine contains two pyridyl and one aniline donor ligand to form a complex of the form [ZnL2]2+. The X-ray structure shows a distorted octahedral metal center with each ligand twisting from planar to accommodate the meridional binding.215... 

As shown in Table 3, triplet lb is computed to be 25-26 kcal/mol lower in enthalpy than triplet lc.77 Table 3 also shows that radicals 8b and 8c, formed by adding a hydrogen atom to lb and lc, respectively, differ in enthalpy by only 1-3 kcal/mol. Therefore, the large enthalpy difference between 3lb and 3lc is not due to a difference between the abilities of the phenyl and pyridyl groups to stabilize an unpaired tt electron. Instead it must reflect an intrinsic enthalpy difference between arylnitrenes and arylcarbenes. Table 3 also shows that aniline (9b) and fl-picoline (9c) are also predicted to have very similar enthalpies, thus providing further evidence that the large enthalpy difference between lb and lc is, indeed, due to the fact that lb is a nitrene, while lc is a carbene. 

As the singlet-triplet splitting of phenylnitrene is 18 kcal/mol, one can deduce that singlet phenylnitrene is 11.4—13.4 kcal/mol more stable than singlet pyridyl-carbene. However, the corresponding radicals, anilines, and substituted pyridines... 

R = Ph) is the most widely investigated of these compounds and serves as a suitable reference compound. Kalb and Bayer3 reported the methanol, ammonia, aniline, and sodium bisulfite adducts of this compound. The reactivity of the indolone increases when the electron density at the 2-position is reduced. In these cases (158 R = 4-nitrophenyl, 2-pyridyl, C02alkyl),49,61,62,91 the indolone adducts (175 Nu = OH, OEt) are stable and isolable the free indolones do not exist. The 2-alkylindolones (158 R = alkyl), in which the conjugation of the azomethine group is less extensive, are also very reactive. They too are only isolated as adducts (175 R = alkyl Nu = OH) with the exception of 158 (R = 1-Bu, Section IV,A,2). 

Besides benzalanilines, also anils derived from heterocyclic aldehydes may be employed (Table VI), as, for example, in the reactions of 4,5-diphenyl-2-(p-tolyl)oxazole (58) with SchifFs bases from p-chloro-aniline and 3-formylpyridine and 2-formylthiophene, leading, respectively, to the /3-(3-pyridyl)-4-(4,5-diphenyloxazol-2-yl)styrene (59) 33 and the /S-(2-thienyI) analog (60).11... 

Of the pyridine aldehydes, only Schiff s bases (192) from 3-formyl-pyridine and anilines such as p-chloroaniline, which with the stilbazole 190 forms l,4-bis[/3-(3-pyridyl)vinyl]benzene (193), have been found to undergo the Anil Synthesis.34... 

The cycloaddition of diazomethane to SchifT bases from heterocyclic aldehydes and anilines provides a useful route to heterocyclic substituted triazolines. Unlike olefins bearing heterocyclic substituents, the heterocyclic imines can be obtained readily by reaction of the appropriate aldehyde and amine thus the diazomethane-imine addition has greater scope than the olefin-azide reaction. NMR spectroscopic studies of the orientation of addition are in accord with previously reported mechanistic considerations (see, e.g., Scheme 93).329 In addition to the influence of the N-aryl group, the electron-withdrawing power of the heterocyclic substituent on the Schiff-base carbon also has a substantial effect on imine reactivity, in the order 2-quinolyl 2-, 3-, or 4-pyridyl > phenyl > 2-thienyl as 2-furyl.329... 

The indane derivative (R)-4-[l-(3-(2-indanyloxy)-4-methoxyphenyl)-2-(4-pyridyl) ethyl]aniline, (III), and derivatives (2) have been prepared and is described. 

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