The photosubstitution reactions of rhodium(III) ammine complexes: A case study

Abstract

This article reviews investigations focused on elucidating the photosubstitution mechanism of the ammine complexes of rhodium (III) in solution. From the State-of-the-Art Symposium: Inorganic Photochemistry, held at the ACS meeting, Seattle, 1983.

Effect of Ring Methylation on the Photophysical, Photochemical and Photobiological Properties of cis-Dichlorobis(1,10-Phenanthroline)Rhodium(III)Chloride†

“…We also observed that the relative amount of minor product formation is greatest at 254 nm (reaching a maximum of 16% for OCTBP) and disappears entirely at 347 nm. The reported (43) wavelength‐dependent photochemistry of [Rh(NH 3 ) 5 I] 2+ provides useful insights for explaining our observations. Irradiation of this complex in the 1 (d‐d) region (λ= 385–470 nm) gives the chemistry shown in () with a quantum efficiency of φ pdt = 0.85.…”

“…In fact, I 2 ‐ had been detected when solutions of aqueous [Rh(NH 3 ) 5 I] 2+ were subjected to flash photolysis in the LMCT region in the presence of traces of I ‐ (44), an indication of electron transfer as a primary photochemical event. Thus, although the net photoreaction is NH 3 substitution, the mechanism is proposed to involve an intermediate resulting from photoredox processes that proceed via an Rh(II) intermediate (43–45).…”

Progress in Practice: Teaching and Learning with Case Studies

“…In addition, the upcoming profusion of "instructional modules" for chemistry instruction are all based on integrating chemistry into a narrative and often socially relevant situation. In another sense, many authors have used the term "case study" colloquially, meaning "an example of" a phenomenon that they wanted to illustrate [18][19][20][21][22][23][24][25][26], as in "the case of DDT" or "a case study on molecular hydrogen calculations. "…”

Photochemistry and Photophysics of Coordination Compounds: Rhodium

“…They have low-lying metal centered (MC) excited stats of dd type, and can be considered paradigmatic representatives of the ligand-field photochemistry of d 6 metal complexes. The subject has been summarized and clearly discussed by Ford and coworkers in their 1983 review articles [7,8]. In more recent times, however, despite a number of interesting investigations [9][10][11][12][13][14][15][16][17][18], the activity in the field seems to have slowed down considerably.…”

“…The Rh(I)-Rh(I) species of formula Rh 2 (bridge) 4 2+ , where the two d 8 metal centers are bridged by four bidentate ligands (e.g., diisocyanoalkanes) in square planar coordination, have dσ * → pσ excited states with a greatly shortened metal-metal bond [19] that emit efficiently in fluid solution [20]. In the Rh(II)-Rh(II) species of formula Rh 2 (bridge) 4 X 2 n+ , the two d 7 metal centers are bridged by four bidentate ligands (e.g., diisocyanoalkanes, acetate) and complete their pseudo-octahedral coordination with a metal-metal bond and two-axial monodentate ligands (e.g., X = Cl, Br n = 2). These dirhodium complexes have long-lived excited states of dπ * → dσ * type, which do not emit in fluid solution but can undergo a variety of bimolecular energy and electron transfer reactions [21].…”