Ethyl 2,4-dimethyl-3-nicotinate

Chapter V. Quinaldine (V,2) 2-methyl-, 2 5-dimethyl- and 2-acetyl-thiophene (V,8-V,10) 2 5-dimethyl and 2 4-dimethyl-dicarbethoxy-p3nrole (V,12-V,13) 2-amino- and 2 4 dimethyl-thiazole (V,15-V,16) 3 5-dimethyl-pyrazole (V,17) 4-ethylp3rridine (from pyridine) (V,19) n-amyl-pyridines from picolines) (V,28) picolinic, nicotinic and isonicotinic acid (V,21-V,22) (ethyl nicotinate and p-cyanop3n idine (V,23-V,24) uramil (V,25) 4-methyl-(coumarin (V,28) 2-hyi-oxylepidine (V,29). 

The reaction products are 2,4-dimethyl-3-acetylpyridine (11) and ethyl ester of 2,4-dimethyl-3-nicotinic acid (12). 

Reaction of -picoline over degassed Raney nickel was found to give 5,5 -dimethyl-2,2 -bipyridine (5), the structure of which was established by its synthesis from 2-bromo-5-methylpyridine. Oxidation of this dimethyl-2,2 -bipyridine, and similar oxidation of the diethyl-2,2 -bipyridine derived from 3-ethylpyridinc, gave the corresponding dicarboxylic acid and the same acid was produced by the action of degassed Raney nickel on sodium nicotinate (in water) or on ethyl nicotinate. These transformations established the 5,5 -substitution pattern for three 2,2 -bipyridines derived from 3-substituted pyridines but such evidence is not available for the biaryls... 

Chemical Name 3,7-dihydro-1,3-dimethyl-7-[2-[(3-pyridinylmethyl)amino] ethyl] -1H-purine-2,6-dione nicotinate... 

From ethyl l-methylpiperidine-3-carboxylate (which was prepared by hydrogenation of ethyl nicotinate with Ni-catalyst and then by methylation by action dimethyl sulfate) and 2-thienyl magnesium bromide was synthesized l,l-di(thiophen-2-yl)-2-(3 -N-methylpiperidine), 3-(di-2-thienylmethylene)-l-methylpiperidine was obtained by dehydration of l,l-di(thiophen-2-yl)-2-(3 -N-methylpiperidine) by action of base. 

Dimethyl acetonedicarboxylate or ethyl acetoacetate can provide the 3-, 4-, and 5-carbons to give 3,5-disubstituted-4-pyridones (XI-177, Rs = CH3CO, CO2CH3). s-Triazine has been used to provide the 2- and 6-carbons. A compound, previously described as 4-hydroxy-3-pyridinecai o lic acid (XII-177, R = Rj = H) ° was shown to be nicotinic acid-l-oxide(XII-I78). ° ... 

Pyridines and pyrazines, such as 2-ethylpyridine, 2,3,5-trimethyl pyridine, 2-ethyl-3,5-dimethyl pyridine, 2,3-dimethylpyrazine and 2,5-dimethylpyrazine, are the most prominent classes of odorous compounds identified as being responsible for the odour of a cigar smoker s breath. They may be generated during cigar pyrrolysis by cleavage of nicotine or by Maillard reaction. 

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