Unlike the two papers Highlighted above, Glorius and co-workers used a substrate functionalised with a chiral auxiliary and achiral heterogeneous catalysts in their asymmetric hydrogenation studies. Thuspyridines functionalized in the 2-position with oxazolidinones were reduced to piperidines under acidic conditions, generally with high stereoselectivities (for example, Reaction 3, Angew Chem Int Ed 2004, 43, 2850). Acid is quite important in this process; without it, the stereoselectivities are reduced, possibly because the system cannot 'lock' into the H-bonded pyridinium form 3.

Pyridine and its derivatives include pyridine, 2-methyl pyridine, 3-methyl pyridine, 4-methyl pyridine and 2-methyl-5-pyridine.

Pyridine compounds are first extracted from coal tar. With the demand increase in the economic growth and the development of synthesis technologies, synthetic pyridine occupies a major share in output and consumption in the world today. Aluminum