| Recent work has uncovered a synthetic route to a new series of meridionally coordinated tridentate terpyridine rhenium dicarbonyl complexes. The complex mer,cis-Re(tpy-κ3N)(CO) 2Cl (1) undergoes facile chloride substitution to produce a variety of complexes of the type mer,cis-[Re(tpy-κ 3N)(CO)2(L)]n, where L = CF3SO3 (2), CH3CN ( 3), CN (4), NC5H5 (5), PMe3 (6), PEt3 (7), PPh 3 (8), P(OMe)3 (9), P(OEt) 3 (10), P(OPh)3 (11), P(O iPr)3 (12), P(OMe)(Ph)2 ( 13). Complexes 1-13 absorb light throughout a significant portion of the visible spectrum. The electrochemistry of these compounds is discussed in relation to their observed π-acidity and their ability to significantly stabilize the lower oxidation state of rhenium relative to the tricarbonyl bipyridine systems. The complex mer,cis-Re(tpy-κ 3N)(CO)2Cl (1) produces a first oxidation potential (reversible) that is 0.85 V (vs. SCE) less oxidizing relative to fac-Re(bpy)(CO)3Cl's first oxidation potential (irreversible). |
