Leaner, meaner cisplatin: Dissociative electron attachment to the anticancer drug cisplatin (1) shows intense resonances at very low energies, which result in PtCl bond cleavage. A single low‐energy electron can trigger the loss of both chlorine atoms from cisplatin (see scheme), thereby forming [Pt(NH3)2]−. This complex is the reactive intermediate to form cisplatin–DNA adducts, which consequently inhibit DNA replication.

Low energy electron attachment to acetamide and some of its derivatives shows unique features in that the unimolecular reactions of the transient anions are remarkably complex, involving multiple bond cleavages and the formation of new molecules. Each of the three compounds acetamide (CH(3)C(O)NH(2)), glycolamide (CH(2)OHC(O)NH(2)) and cyanoacetamide (CH(2)CNC(O)NH(2)) shows a pronounced resonance located near 2 eV and decomposing into CN(-) along a concerted reaction forming a neutral H(2)O molecule and the corresponding radical (methyl and methoxy). From glycolamide an additional reaction pathway resulting in the loss of water is operative, in this case generating two fragments and observable via the complementary anion (M-H(2)O)(-). The pseudohalogen OCN(-) is formed at comparatively lower intensity having a specific energy profile for each of the target molecules. In dibromocyanoacetamide (CBr(2)CNC(O)NH(2)) the situation changes completely as now comparatively intense CN(-) and OCN(-) signals appear already near zero eV. Electronic structure calculations predict that in dibromocyanoacetamide the extra electron resides in a molecular orbital (MO) which is strongly localized at the Br sites. For the other compounds, the relevant MOs are appreciably delocalized showing pi*(C=O) character.

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