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Two new methods of predicting free radical polymerizability of allyl monomers have been developed. MINDO/3 calculations of eigenvalues for the C—H bond a to the atlyl substituent allow comparison of relative bond strengths. Monomers known to undergo degradative chain transfer display more positive eigenvalues correlating with weaker α‐C—H bonds. Polymerizable monomers have more negative eigenvalues and stronger α‐C—H bonds. The latter possess strongly polarized or protonated substituents not capable of resonance stabilization of a chain‐terminating allyl radical. The inductive effect of such substituents on the 13C NMR peaks of the vinyl carbons is the basis for the empirical spectroscopic method. Allyl compounds display β‐carbon peaks farther downfield than the γ‐carbon peaks. Polymerizable monomers generally have β peaks shifted upfield and γ peaks shifted downfield from those of poor monomers. This effect brings the two peaks closer together in the spectrum. Thus, the smaller the Δδ value (δβ − δγ), the more likely the monomer is to polymerize well. Monomers with intermediate eigenvalues or Δδ values may polymerize with difficulty or only under special conditions. Combined use of the theoretical and empirical techniques can allow prediction of inherent polymerizability and can facilitate evaluation of reaction media most favorable to polymer formation.

44Dialkylamino)pyridines have been used as supernucleophilic catalysts in a large number of reactions. In many systems, these catalysts provide a level of reactivity combined with selectivity that is unique. Several reviews of the synthesis and a p plications of these catalysts have appearedJ3 Facile commercial synthesis has made dimethylaminopyridine (1, DMAP) the most popular member of this class of supernucleophiles, although the pyrrolidine analog (2, PPY) is the most active. Both steric and electronic arguments have been put forth to explain its enhanced catalytic activity compared with DMAP.' 0 1 2Three main types of polymer-bound dialkylaminopyridines, have been reported. The first4s5 dealt with reaction of several carboxylic acid-containing dialkylaminopyridines with commercial polyethyleneimine (PEI) to give reagents of general structure 3. These compounds were examined for catalytic behavior in the hydrolysis of p-nitrophenyl esters and found to be highly active. 0 I 1 PE I N c R NR' 3 4The other two reports dealt with incorporation of the dialkylaminopyridine moiety into typical functionalized, crosslinked polystyrene (4) by both reaction on preformed polymel.6.' and synthesis of a monomer and subsequent copolymerization! Application of these catalysts to esterification reactions, under Michaelis-Menten conditions, yielded results comparable to those obtained with the corresponding small molecular analogs.The polymeric catalysts synthesized in these reports have several limitations arising from the nature of the substrate polymer. First, two of these p o l y m e w

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