Pyridine-3-carboxylic acid, 4-benzoyl

D-Arg h2N.cooh L-NyNH2 NH Isonicotinic acid Cl XOOH 3-Benzoyl-2-pyridine carboxylic acid o CP COOH ... 

P-Acetoxy-5-hydroxy-B-mrcholestan-6-carboxylic Acid 5,6-Lactone (TO)."" A solution of 5 g (0.011 mole) of keto acid (69), 4.4 g of benzoyl chloride and 10 ml of anhydrous pyridine is allowed to stand for 3 days at room temperature. After a short period the mixture turns red-brown and at the end of the reaction the dark semi-solid mass is poured into 200 ml of water and extracted with two 100 ml portions of ether. The ethereal extracts are washed twice with equal portions of 5 % sodium hydroxide and water, dried and the ether evaporated. The red sirupy residue is mixed with 10 ml of methanol and a brown solid separates immediately. After standing for 1 hr the solid is removed by filtration and washed with methanol. A second crop is obtained upon concentration of the filtrate. The combined crops are recrystallized twice from methanol to give (70) as white needles mp 124-125° yield 2.8 g (58 %). 

Amination (11) and solution carbonation (8) reactions were carried out as described previously. For solid-state carbonations, a benzene solution of poly(styryl)lithium was freeze-dried on the vacuum line followed by introduction of high-purity, gaseous carbon dioxide (Air Products, 99.99% pure). Analysis and characterization of polymeric amines (11) and carboxylic acids (8) were performed as described previously. Benzoyl derivatives of the aminated polystyrenes were prepared in toluene/pyridine (2/1. v/v) mixtures with benzoyl chloride (Aldrich, 99%). 

Another derivative was synthesized starting from 5-aminopyridazine-4-carboxylic acid (156). Its reaction with benzoyl chloride in pyridine gave 2-phenylpyridazino[4,5-[Pg.762]

Pyrazolo[3,4-Z)]pyridines, the 7-chloro-6-fluoro-2,4-dimethylquinoline and its mercapto-thiadiazolyl or oxadiazolyl quinolines 21 were prepared via Diels-Alder reaction conversion of methyl 2-(3-oxo-3-phenylpropenylamino)benzoate into 3-benzoyl-l.S -quinolin-4-one 22 . A mixture of aniline derivatives and malonic ester gave a variety of 3-aryl-4-hydroxyquinolin-2(l//)-ones 23. Condensation of isatins with ketones afforded quinoline-4-carboxylic acids. 2-Aryl-l,2,3,4-tetrahydro-4-quinolinones 22 and carbazolylquinolone were also prepared. The substitution of 2-chloroquinoline gave the 2-substituted quinolines. Basic alumina has catalyzed the C-C bond formation between 2-hydroxy-1,4-naphthoquinone and 2-chloroquinoline derivative to give 21. Reaction of organic halides with 8-hydroxyquinolines gave the respective ethers. The azodye derivatives of 21 were prepared in the absence of solvent. Silica gel catalyzed the formation of 2-ketomethylquinolines from reaction of 2-methylquinolines with acyl chlorides. 

In a similar fashion, as carboxylic acids or their esters, certain carboxamides possessing an ortho acyl group tnay also cyclocondense with hydrazine. Thus, Ar,/V-dicthyl-3-(2-pyridy car-bonyl)pyridine-2-carboxamide gives the corresponding pyrido[2,3-(i]pyridazin-H(7//)-one 15 in 89% yield, whereas, in contrast, 3-benzoyl-A, Ar-diisopropylpyridine-2-carboxamide and hydrazine give jV,2V-diisopropyl-5-phenylpyrido[2,3-d]pyridazin-8-amine (16) in 42% yield.50... 

Of the aromatic dibasic acids, the three phthalic acids on treatment with hydrazoic acid yield the corresponding aminobenzoic acids with mere traces of the diaminobenzenes. > Anthranilic acid and its derivatives in which one hydrogen on the amino group is replaced by acetyl, benzoyl, or p-toluyl are inert to hydrazoic acid. These compounds thus resemble in activity a-amino acids and their derivatives in the aliphatic series. The following pyridine and quinoline acids resemble -amino acids and also do not react pyridine-2-carboxylic acid, pyridine-2,3-... 

The reaction of acyl halides with carboxylic acids affords good yields of simple and mixed anhydrides. The use of pyridine or triethylamine helps to remove the hydrogen chloride by-product. However, the preparation of benzoic anhydride from benzoic acid and benzoyl chloride has also been carried out in the absence of trialkylamines by heating under reduced pressure, in the presence of zinc chloride or by refluxing in chlorohydrocarbons such as methylene chloride. 

Poly(methyl 3-(l-oxypyridinyl)siloxane) was synthesized and shown to have catalytic activity in transacylation reactions of carboxylic and phosphoric acid derivatives. 3-(Methyldichlorosilyl)pyridine (1) was made by metallation of 3-bromopyridine with n-BuLi followed by reaction with excess MeSiCl3. 1 was hydrolyzed in aqueous ammonia to give hydroxyl terminated poly(methyl 3-pyridinylsiloxane) (2) which was end-blocked to polymer 3 with (Me3Si)2NH and Me3SiCl. Polymer 3 was N-oxidized with m-ClC6H4C03H to give 4. Species 1-4 were characterized by IR and H NMR spectra. MS of 1 and thermal analysis (DSC and TGA) of 2-4 are discussed. 3-(Trimethylsilyl)-pyridine 1-oxide (6), l,3-dimethyl-l,3-bis-3-(l-oxypyridinyl) disiloxane (7) and 4 were effective catalysts for conversion of benzoyl chloride to benzoic anhydride in CH2Cl2/aqueous NaHCC>3 suspensions and for hydrolysis of diphenyl phosphorochloridate in aqueous NaHCC>3. The latter had a ti/2 of less than 10 min at 23°C. 

A mechanism (Scheme 11) similar to the generally accepted PTC process (Scheme 1) has been developed to explain anhydride formation (30). Acid chlorides such as benzoyl chloride have a low solubility in water and, therefore, are concentrated in the dichloromethane layer. In the absence of a catalyst, benzoyl chloride is relatively inert to anhydride formation or hydrolysis under comparable experimental conditions (Table 1). However, pyridine 1-oxide, which distributes relatively uniformly between the two layers, reacts quickly with the acid chloride to form 1-acyloxypyridinium chloride (2) in the dichloromethane layer. Intermediate 2 dissolves preferentially in the aqueous layer, where it rapidly reacts with carboxylate ion to form the anhydride and releases the catalyst (35). 

Carboxylation of the potassium salt of 3-hydroxy-6-methylpyridine (145) gave the picolinic acid 146(84MI16). The Hammick condensation reaction of picolinic acid with benzaldehyde has been studied with regard to the effect of solvent, temperature, and molar ratio of reactants (85MI5). Benzoyl chloride, or benzaldehyde, and l-benzyl-4,6-diphenylpyridinium-2-carboxylate afford 2-benzoyl-4,6-diphenylpyridine (85JCS(P1)2167). Sulfur and 1,4,6-triaryl-pyridinium-2-carboxylates 147 in xylene at 140°C give the corresponding pyridine-2-thiones 148(838149). 

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