Photorelease of nitric oxide in water-soluble diruthenium nitrosyl complexes with phosphonate substituted pyridylpyrrole

• Published in: Inorganica Chimica Acta 2022-05, Vol.534, p.120826, Article 120826
• Main Authors: Ma, Fan, Zhang, Ting-Ting, Zhang, Zheng-Hao, Tong, Hai-Xia, Yi, Xiao-Yi
• Format: Article
• Language: English
• Subjects: Coordination compounds; Crystal structure; Diruthenium; Ligands; Nitric oxide; Nitrosyl; NMR; Nuclear magnetic resonance; Palladium; Phosphonate ligand; Phosphonates; Photorelease; Refluxing; Ruthenium; Scavenging; Single crystals; Structural analysis; Substitutes; Toluene; Triethylamine; Water chemistry; Water-soluble metal complex
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/j.ica.2022.120826

Diruthenium nitrosyl complex [1]·(Et3NH)2 with phosphonate substituted pyridylpyrrole is water-soluble, and featured of {RuII-NO+}6 core structure and NO release upon irradiation. The amount of photoreleased NO was determined by Griess reaction and DPPH radical scavenging reaction. [Display omitted] •Phosphonate ligands substituted pyridylpyrrole and its diruthenium nitrosyl complexes [1]·(Et3NH)2 were synthesized.•Complex [1]·(Et3NH)2) is water-soluble, and featured of {RuII-NO+}6 core structure and NO release upon irradiation.•The amount of photoreleased NO was determined by Griess reaction and DPPH radical scavenging reaction. The diethylphosphonate ligand HL1 substituted pyridylpyrrole was synthesized by treatment of 2-bromo-6-(1H'-pyrrol-2-yl)pyridine and diethylphosphite in presence of base triethylamine and catalyst Pd(PPh3)4 under refluxing toluene conditions. The HL1 ligand was treated with bromotrimethylsilane and followed by hydrolysis with methanol to afford the diphosphonic acid ligand H3L2. Treatment of H3L2 with [Ru(NO)Cl3] in presence of triethylamine in refluxing thf was generated diruthenium nitrosyl complex [Ru(L2)(NO)(Cl)]2·(Et3NH)2 ([1]·(Et3NH)2), which is water soluble. The ligands and metal complex were fully characterized by NMR, IR, ESI-MS and single crystal X-ray diffraction technology. The solid-state structure analysis displays 12- is dinuclear species, of which two ruthenium atoms are linked by two PO32- groups. Photorelease of nitric oxide from 12- was monitored by UV–Vis spectra and the amount of the NO was determined by the Griess reaction and DPPH radical scavenging reaction.