need to be sulfonated in order to produce the stable polysemiquinone form of the polymer. Indeed, additional sulfonation and consequent protonation of amine nitrogen atoms would convert some of the -(NH)to -(NH2+)groups and hence destabilize the polymer by reducing the extent of its tr conjugation. The absorption maxima at 1080, 700, and 620 cm"1 in the FTIR spectrum of compound , are consistent with the presence9 of S03" groups attached to the aromatic rings. The absorption maxima at 820 and 870 cm"1 indicative of 1,2,4-trisubstitution of the rings are out-of-plane bending of aromatic hydrogens. These absorptions are not present in the 1,2-disubstituted emeraldine base (II), from which compound , was synthesized.

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New strategies for the synthesis of (trialkylsilyl)vinylketenes ("TAS-vinylketenes") are described based on the photochemical Wolff rearrangement of R′-silyl-R′-diazo-R,β-unsaturated ketones and the 4π electrocyclic ring opening of cyclobutenones. These remarkably robust vinylketenes undergo highly regioselective [4 + 2] cycloadditions with reactive olefinic and acetylenic dienophiles to produce highly substituted cyclohexenones and phenols in which the ketene carbonyl dominates in controlling the regiochemical course of the reaction. The stereochemical course of these cycloadditions follows the Alder endo rule, as illustrated in the reaction of nitropropene with TASvinylketene 22.

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