Photosubstitution and Photoisomerization

An interesting alternative mechanism of activation is the photochemical reduction of Pt(IV) to Pt(II) (Fig. 3). In addition to photoreduction, photosubstitution and photoisomerization can also occur, making the photochemistry of Pt complexes difficult to predict and a careful analysis of the photoproducts imperative (21). We have been involved particularly in the development of photochemotherapeutic agents based on Pt(IV) and the study of their photodecomposition and (subsequent) interactions with... 

Fig. 3. Photoactivation of Pt(IV) complexes as a prodrug strategy for metallochemotherapeutics (a) general scheme of prodrug activation by photoreduction (b) photosubstitution and photoisomerization are competing photoreaction pathways, which can result in different reactive species upon reduction (c) an example of a photoactive platinum(IV) diazido complex developed in our lab.

Photosubstitution and Photoisomerization Reactions ofd6 Metal Complexes Fowles, G. W. A., Reaction by Metal Hallides with Ammonia and Aliphatic 30 213... 

Ford, Peter C., Wink, David, and DiBenedetto, John. Mechanistic Aspects of the Photosubstitution and Photoisomerization Reactions oj if... 

Styrylpyridine photochemistry has been important in one other system. The photoprocesses in the complexes W(CO)sX (X = pyridine, 2-styrylpyridine, and 4-styrylpyridine) have been investigated.129 Unlike the XRe(CO)3(taz s-styryl-pyridine)2 and Ru(II)-styrylpyridine complexes having lowest IL and CT states, respectively, the W(CO)5X complexes have lowest LF excited states with only a small contribution from W - pyridyl CT. The one-electron diagram for low-spin d6, Cnv complexes shown in Scheme 7 is appropriate here. Both photosubstitution and photoisomerization reactions are found for the W(CO)5X complexes and some quantum yield data are found in Table 23.129 The data show that substitution efficiencies for... 

Current knowledge of chromium(lll) photochemistry relates mostly to the decay of the metal-centered (MC) excited states (246). Photosubstitution and photoisomerization are, however, of minor... 

Photosubstitution and Photoisomerization 13.2.3. with Group VIII Complexes... 

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