| Abstract
| - The self-exchange electron-transfer (ET) rate constantk22 for 1,2,3,4,5-pentamethylferrocenewasdetermined by NMR line broadening to be 8.5(±0.8) ×106 M-1s-1 (25 °C, CD3CN/0.09 MEt4NBF4)and k11 for the bis-N,N-bicyclic hydrazine,9,9‘-bi-9-azabicyclo[3.3.1]nonane, to be 8.7(0.5) ×103M-1 s-1 (25 °C,CH2Cl2). These self-exchange rateconstants are used to analyze cross reactions ofthese molecules with hydrazines, ferrocenes, andtetramethyl-p-phenylenediamine (TMPD)usingMarcus theory. Cross-reaction rate constants for eight reactionsare reported. Included are sixcross-reactions between methylferrocenes and four cyclic hydrazines,one hydrazine, hydrazine−reaction, and the reduction of TMPD+by a cyclic hydrazine. These are the firstcross-reactionrate constants reported for hydrazine−hydrazine andhydrazine−TMPD+ ET reactions.The cross-reaction rate constants are used to test the application of Marcustheory to hydrazine ET reactionsand to extract estimates of hydrazine self-exchange ET rate constantsin systems for which directmeasurement is presently impossible.
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