Photochemistry of rhodium(I) olefin complexes containing the (hydro)tris(pyrazolyl)borate ligand

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Vol. 135; no. 2; pp. 179 - 183
• Main Authors: Boaretto, Rita, Ferrari, Arlen, Merlin, Massimo, Sostero, Silvana, Traverso, Orazio
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 2000; Elsevier Science
• Subjects: Absorption spectra; Chemistry; Exact sciences and technology; General and physical chemistry; Photochemistry; Photolysis; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Rh(III) complex; Photolysis; Rh(III) complex; Absorption spectra; Intramolecular reaction; Isomerization; Organic ligand; Transition metal Complexes; Photochemical reaction; Experimental study; Organic solvent; Near ultraviolet radiation; Rhodium Complexes; Benzene; Complexes Mixed; Reaction mechanism; Platinoid Complexes; Hapto complex; Kinetics; Ultraviolet visible spectrometry
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/S1010-6030(00)00301-4

The photoisomerisation ( λ=400 nm) of [Tp Me2Rh (η 4-1,5-COD)] ( 1), (Tp Me2=hydrotris(3,5-dimethyl)pyrazolyl borate, 1,5-COD=1,5-cyclooctadiene) to [Tp Me2Rh (η 4-1,3-COD)] ( 2) is reported. The photoreaction is an intramolecular (3,4) hydrogen shift of the coordinated 1,5-COD possibly involving an allylrhodium(III) intermediate. The selective photolysis of complex 2 with 336 nm light causes the dissociation of 1,3-COD forming the organometallic fragment {Tp Me2Rh} ( A) as its primary photoproduct. Fragment A is a versatile entry point in the photochemical preparation of new hydrido Rh(III) complexes.