Abstract
The photoinduced nucleophilic substitution reactions of 3-nitroanisole (3-NA) in the presence of OH − in mixtures of H 2O and CH 3CN and in the presence of OCH 3 − in CH 3OH were investigated by nanosecond time-resolved absorption spectroscopy. The absorption spectra of the solution recorded just after the triplet state of 3-NA has disappeared reveal that the formation of the substitution product is complete at that stage. We conclude that the addition of the nucleophile to the ring carbon atom C-1 is the rate-determining step in the methoxy substitution reactions of 3-NA in H 2O and CH 3OH. As well as the addition to C-1 there is at least one competing reaction of the nucleophile with the triplet state. This reaction, which reduces the overall quantum yield of the substitution reaction, leads to the formation of long-lived species (λ max = 370 nm). Analysis of previously reported results for the photosubstitution reactions of 3,5-dinitroanisole in the presence of OH − and triethylamine shows that they can also be explained by the mechanism for the substitution reactions of 3-NA.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
