Oxazolidine acrylamides

Although the free-radical polymerization of MMA typically exhibits a syndiotactic bias (rr triad content = 60%-70%), it has long been known that the stereochemical interactions between the chain-end radical and vinyl monomers in free-radical polymerization can be modified by using chiral protecting groups. For example, the 80 °C AIBN-initiated polymerization (AIBN = 2,2 -azobisisobutyronitrile) of oxazolidine acrylamides based on valine and t rt-leucine ultimately yields highly isotactic (92% m dyad content) poly(acrylic acid) and PMA after chemical modification (Scheme 23.23). " ... 

SCHEME 23.23 The free-radical polymerization of oxazolidine acrylamide monomers and conversion of the polymers into highly isotactic poly(acryhc acid) and PMA. 

Oxazolidin-5-one Intermediates. Several workers have demonstrated the significance of an inframolecular cyclization (Scheme 8) in the Schiff base form of aldosyl-a-amino acids, as an intermediate step of the Amadori rearrangement, which is accompanied by decarboxylation of the amino acid. One important example of the reaction is a pathway for acrylamide formation from D-glucose and L-asparagine in fried foods, such as potatoes. 

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