Protonation of the symmetrical tetraphosphine complexes Fe 2(S2CnH2n)(CO)2(dppv) 2 afforded the corresponding terminal hydrides, establishing that even symmetrical diiron(I) dithiolates undergo protonation at terminal sites. The terminal hydride [HFe2(S2C3H 6)(CO)2(dppv)2]+ was found to catalyze proton reduction at potentials 200 mV milder than the isomeric bridging hydride, thereby establishing a thermodynamic advantage for catalysis operating via terminal hydride. The azadithiolate protonates to afford, [Fe 2[(SCH2)2NH2](CO) 2(dppv)2]+, [HFe2[(SCH 2)2NH](CO)2-(dppv)2]+, and [HFe2[(SCH2)2NH2](CO) 2(dppv)2]2+, depending on conditions.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry