Multistep Photochemical Reactions of Polypyridine-Based Ruthenium Nitrosyl Complexes in Dimethylsulfoxide

Nataliia Marchenko (1) , Pascal G. Lacroix (1) , Valerii Bukhanko (1) , Marine Tassé (1) , Carine Guyard-Duhayon (1) , Martial Boggio-Pasqua (2) , Isabelle Malfant (1)

1 LCC - Laboratoire de chimie de coordination
2 PTC - Photochimie théorique et computationnelle (LCPQ)

The photorelease of nitric oxide (NO·) has been investigated in dimethylsulfoxide (DMSO) on two compounds of formula [Ru(R-tpy)(bpy)(NO)](PF6)3, in which bpy stands for 2,2′-bipyridine and R-tpy for the 4′-R-2,2′:6′,2″-terpyridine with R = H and MeOPh. It is observed that both complexes are extremely sensitive to traces of water, leading to an equilibrium between [Ru(NO)] and [Ru(NO2)]. The photoproducts of formula [Ru(R-tpy)(bpy)(DMSO)](PF6)2 are further subjected to a photoreaction leading to a reversible linkage isomerization between the stable Ru-DMSO(S) (sulfur linked) and the metastable Ru-DMSO(O) (oxygen linked) species. A set of 4 [Ru(R-tpy)(bpy)(DMSO)]2+ complexes (R = H, MeOPh, BrPh, NO2Ph) is investigated to characterize the ratio and mechanism of the isomerization which is tentatively related to the difference in absorbance between the Ru-DMSO(S) and Ru-DMSO(O) forms. In addition, the X-ray crystal structures of [Ru(tpy)(bpy)(NO)](PF6)3 and [Ru(MeOPh-tpy)(bpy)(DMSO(S))](PF6)2 are presented.

Mots clés: nitric oxide; DFT computations; photochemistry; ruthenium complexes

Domaines: Chimie de coordination

Nataliia Marchenko, Pascal G. Lacroix, Valerii Bukhanko, Marine Tassé, Carine Guyard-Duhayon, et al.. Multistep Photochemical Reactions of Polypyridine-Based Ruthenium Nitrosyl Complexes in Dimethylsulfoxide. Molecules, 2020, 25 (9), pp.2205. ⟨10.3390/molecules25092205⟩. ⟨hal-02611130⟩