Transformations of functional groups, such as OCH2Ph, OCOPh, NO2 and I, in 1,3,5-triphenyl-6-oxoverdazyls 1a-1e were investigated in order to expand the range of synthetic tools for incorporation of the verdazyl system into more complex molecular architectures and to increase spin delocalization. Thus, Pd-catalyzed debenzylation of the OCH2Ph group or basic hydrolysis of the OCOPh group gave the phenol functionality, which was acylated, but could not be alkylated. Orthogonal deprotection of diphenol functionality was also demonstrated in radical 1c. Pt-catalyzed reduction of the NO2 group led to the aniline derivative, which was acylated. Attempted C-C coupling reactions to iodophenyl derivatives 1e and 5e were unsuccessful. Selected verdazyl radicals were characterized by EPR and electronic absorption spectroscopy, and results were analyzed with the aid of DFT computational methods.

A series of phenyl/hetaryl and bishetaryl thioketones have been prepared via oxygen/sulfur exchange of the corresponding ketones by treatment with Lawesson's reagent. The nonsymmetrical ketones were conveniently accessible via the reactions of lithiated furan, thiophene, and selenophene with N,N-dimethylbenzamide and hetarylcarboxamides, respectively, whereas the symmetrical ketones were obtained by treatment of ethyl N,N-dimethylcarbamate with 2 equiv of lithiated heterocycles. Under typical conditions, selected examples of the hetaryl thioketones were oxidized selectively to give thiocarbonyl S-oxides (sulfines). Reactions with diazomethane at -65°C yielded 1,3-dithiolanes in a regioselective manner and hetero-Diels-Alder reactions of 2-thienyl substituted thioketones with dimethyl acetylenedicarboxylate yielded the corresponding 7H-thieno [2,3-c]

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Ferrocenyl-and hetaryl-substituted ketones react smoothly with the Ruppert-Prakash reagent and, after desilylation of the intermediate adduct, gave the corresponding tertiary 2,2,2-trifluoroethanols. Similarly, ferrocenyl carbaldehyde was converted into 1-ferrocenyl-2,2,2-trifluoroethanol via nucleophilic trifluoromethylation. Some of the obtained fluorinated alcohols were transformed into thiols by treatment with Lawesson's reagent or P2S5•2C5H5N complex. Remarkably, the obtained thiols are non-odorous compounds.

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