Picoline phenylation

The reactivity of the 1-methyl group and of corresponding positions (i.e., a-carbon atoms) in other l-alkyl-j8-carbolines, analogous to that in a-picoline, quinaldine, and isoquinaldine, is due to the acidity of this center. Deprotonation yields a resonance-stabilized anion (288) which reacts readily with electrophilic reagents. Metallation with phenyl-lithium of the 1-methyl group of a l-methyl-j8-carboline derivative in which the indole nitrogen is protected, first described by Woodward... 

Further organic storing materials Phenyl bromide [14], pyridine, 1 -picoline, 2,6-lutidine [15-17] Arsonium salts [18, 19] Phosphonium salts [20] Pyridinium bromides [21] Aromatic amines [22] Urotropin-bromine adduct [23] Pyridinium and sulfonium salts [24] Propionitril [25]... 

The aliphatic hydrogens of a-picoline (1) are relatively acidic, so that treatment with phenyl lithium... 

Metalation of a-picoline by phenyl lithium, 23, 84 Metal bath, 20, 48... 

Methyl phenyl ether, m55 Methyl phenyl ketone, a31 2-Methyl-2-phenylpropane, b523 Methyl y-picolinate, m413... 

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. 

The electrochemical oxidation of diethyl 7V,jV-bis(2,4,6-trimethoxy-phenyl)aminomethylmalonate in acetonitrile in the presence of lithium perchlorate and 4-picoline gave A[,A/-bis(2,4,6-trimethoxyphenyl)amino-methylenemalonate in 76% yield (81MI4). 

Phenylbenzbyldiazomethane, 48 Phenyl cinnamate, 77 o-Phenylenediamine, 10 Phosphorus oxychloride, 11 Phosphorus trichloride, 106 Photoflood lamps, 84, 104 Phthalic anhydride, 70 Phthalic monoperacid, 70 Phthaloyl chloride, 51 a-Picoline, 79... 

More detailed investigations of the conversion of 1 into 2 have shown that in undisturbed melts an equilibrium exists between the basic form 1 and the acidic form 2 (56JOC654) and that in the presence of a base (pyridine, 4-picoline) nonequilibrium conditions are created, favoring the formation of the acidic form 2 (56JOC654). The presence of substituents in the phenyl ring at position 1 influences the equilibrium between the basic and acidic form (Scheme IV.4). 

Complexes of rhenium(bipyridine)(tricarbonyl)(picoline) units linked covalently to magnesium tetraphenylporphyrins via an amide bond between the bipyridine and one phenyl substituent of the porphyrin 19 exhibited no signs of electronic interaction between the Re(CO)3(bpy) nnits and the metalloporphyrin units in their gronnd states. However, emission spectroscopy revealed a solvent-dependent quenching of porphyrin emission upon irradiation into the long-wavelength absorption bands localized on the porphyrin. 

Torrents, A., and A. T. Stone, Hydrolysis of phenyl picolinate at the mineral/water interface , Environ. Sci. Technol., 25, 143-149 (1991). 

The acidity of the methyl group in 5-methylindolizines is similar to that of 2-picoline (see Section 3.08.1). This has been used to prove the structure of 2-phenyl[2.2.3]cyclazine (95) unambiguously by the two syntheses shown in Scheme 10 (59JA1459). 

A nitrogen common to two rings was obtained by cycloaddition of phenyl isocyanate to 3-picoline TV-oxide.126 Isomeric products 37 and 38 were obtained, the first predominating. Phosgene, acting on an amino-quinoxaline A-oxide, gave a comparable fused ring system.127 Hamana... 

Nicotinic acid has been prepared by the oxidation of nicotine with nitric acid.1 It has also been prepared by the action of potassium permanganate upon /3-picoline, nicotine, lutidine, /3-phenyl pyridine, and /3-dipyridyl2 and by the action of chromic acid upon nicotine and /3-phenyl pyridinecarboxylic acid.3... 

Ethyl pentyl ketone, o35 Ethyl phenyl ether, e28 Ethyl picolinate, e214... 

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