Reaction of anion with monomer

Multiple bonds between the atoms in the molecules of conventional monomers may possess a relative excess or deficiency of electrons. In principle, only a few of these bond types exist nitrile, aldehyde, carbonyl, carboxyl, ester, vinyl and acetylene. In macromolecular chemistry, the reactions of anions with oxiranes, the amide and ester (in rings) and the siloxane bond are also of importance. 

Anion addition to saturated aldehydes, esters and ketones usually occurs at the 1,2 position [202] 

Under certain condittions, deviations from this scheme may occur. 

Ketones with hydrogen in the a position can react as Bronsted acids [203] 

The reactivity of organometals increases in the order Li Na K alkali metal organometals are more efficient than magnesium and aluminium compounds and the reaction of aryllithium organometals with ketones is more rapid than that of alkyllithium compounds [202], Wittig and Bub [204, 205] postulated the formation of transition complexes with simultaneous nucleophilic attack on the carbonyl and electrophilic attack on the oxygen by the metal. 

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