Design of an NO photoinduced releaser xerogel based on the controlled nitric oxide donor trans-[Ru(NO)Cl(cyclam)](PF_6)_2 (cyclam=1,4,8,11-tetraazacyclotetradecane)

摘要

The immobilization and properties of the nitric oxide donor trans-[Ru(NO)Cl(cyclam)](PF_6)_2,Ru-NO,entrapped in a silica matrix by the sol-gel process is reported herein.The entrapped nitrosyl complex was characterized by spectroscopic (UV-vis,infrared (IR),X-ray photoelectron,and ~(13)C and ~(29)Si MAS NMR) and electrochemical techniques.The entrapped species exhibit one characteristic absorption band in the UV-vis region of the electronic spectrum at 354 nm and one IR V_(NO) stretching band at 1865 cm~(-1),as does the Ru-NO species in aqueous solution.Our results show that trans-[Ru(NO)Cl(cyclam)](PF_6)_2 can be entrapped in a SiO_2 matrix with preservation of the molecular structure.However,in a SiO_2/SiNH_2 matrix,the complex undergoes a nucleophilic attack by the amine group at the nitrosonium.Irradiation of the complex,entrapped in the SiO_2 matrix,with light of 334 nm,resulted in NO release.The material was regenerated to its initial nitrosyl form by reaction with nitric oxide.