Elimination of Nitrogen from Azo Compounds and Analogues

The chemistry of the photoactive diazosulfonate group (-Nr-S03 ) and its applications in polymer chemistry have been reviewed by Nuyken and Voit in an article which also contains some experimental details. Polymer applications include photoresins, test stripes for assays of phenolic compounds, and photo-labile surfactants. Novel polyesters with photosensitive backbones based on the 

3 Elimination of Nitrog frwn Diazo Compom and Diazirines 

The photolysis of diazo compounds and the isomeric diazirines continues to attract a great deal of interest, ranging from fundamental theoretical studies to applications such as photoaffinity labelling. 

The photolyses of three p-benzoquinone diazide carboxylic acids (19, R = H, Me, /-Bu) have been studied in low temperature matrices. The general reaction pathway involves primary carbene formation, followed by secondary photodecarboxylation to yield 2,4-didehydrophenols (20), which could be observed directly by IR spectroscopy. 

ESR signal while photolysis at 265 nm yields a different species with a triplet ESR signal, and which is identified as triplet (11). Surprisingly the two spin states of (11) do not equilibrate at 77 K to a measurable extent. It is postulated that the two spin states of (11) differ from each other conformationally, and that the equilibration is impeded when the species are held rigid in low-temperature glasses. 

3 Elimination of Nitrogen from Diazo Compounds and Diazirines 

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