Nicotine chromic acid oxidation

Scheme 15.1 Original chromic acid oxidation of nicotine to nicotinic acid.

Oxidation of nicotine with chromic acid led to the isolation of pyridine-3-carboxylic acid, which was given the trivial name nicotinic acid. We now find that nicotinic acid derivatives, especially nicotinamide, are biochemically important. Nicotinic acid (niacin) is termed vitamin B3, though nicotinamide is also included under the umbrella term vitamin B3 and is the preferred material for dietary supplements. It is common practice to enrich many foodstuffs, including bread, flour, corn, and rice products. Deficiency in nicotinamide leads to pellagra, which manifests itself in diarrhoea, dermatitis, and dementia. 

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... 

A compound prepared and first described as nicotinium dichromate (NDC) by Palomo et al.,379 was later shown by X-ray-crystal analysis380 to be a betainic mixed anhydride of nicotinic and chromic acid (NACAA). Because of its unique structure, it deserves a close scrutiny of its oxidative properties.381 Replacement of the chloride anion in the quaternary ammonium resin, Dowex 1-X8, for the dichromate anion, leads to a polymer supported dichromate, which is able to make selective benzylic oxidations.382 Finally, poly[vinyl(pyridinium dichromate)] (PVPDC), a polymeric analogue of PDC, must be mentioned whose use in the oxidation of alcohols allows for a very easy work-up.383... 

Liquid-Phase Oxidation of Nicotine with Permanganate, Chromic Acid, etc. 

The oxidation of picoline with permanganate or chromic acid suffers from the same drawback, albeit in a lesser form, as nicotine (Scheme 15.2). 

Nicotine is converted by oxidation with chromic acid or permanganate into nicotinic acid (4), and by quaternisation, methylation and subsequent oxidation... 

For the structm-e determination, Carl Huber, Hugo Weidel (1849-1899) and Richard Laiblin oxidised nicotine inter alia with chromic acid and nitric acid, and they obtained pyridine-3-carboxylic acid (nicotinic acid), which is also accessible by oxidation of jS-picoline. 

The same stability principle applies to the historical synthesis of nicotinic acid from nicotine which, for example, upon oxidation with permanganate , chromic acid or fuming nitric acidi , loses four carbons and the N of the 5-membered ring. 

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