Structural Investigation of Photochemical Intermediates in Solution by Cold UV Spectroscopy in the Gas Phase: Photosubstitution of Dicyanobenzenes by Allylsilanes

Autor:	Satoru Muramatsu, Yoshiya Inokuchi, Manabu Abe, Yuma Kitamura
Rok vydání:	2021
Předmět:	Electrospray chemistry.chemical_compound Ultraviolet visible spectroscopy Chemistry Photodissociation Cationic polymerization Physical and Theoretical Chemistry Mass spectrometry Photochemistry Acetonitrile Ion Gas phase
Zdroj:	The Journal of Physical Chemistry A. 125:6238-6245
ISSN:	1520-5215 1089-5639
Popis:	Electrospray ion sources with an in-line quartz cell were constructed to produce photochemical intermediates in solution. These ion sources can detect photochemical intermediates having lifetimes longer than a few seconds. Intermediates formed by photosubstitution of 1,4-dicyanobenzene (DCB) by allyltrimethylsilane (AMS) in acetonitrile using a Xe lamp were injected into the mass spectrometer. The cationic intermediate (C11H10N2·H+) was observed at m/z = 171, but no anionic intermediate was found, although C11H9N2- was expected based on prior studies. Theoretical studies suggested that C11H9N2- was simultaneously converted to neutral C11H10N2 and cationic C11H10N2·H+ species, which can be stable intermediates in the photosubstitution reaction. The UV photodissociation (UVPD) spectrum of C11H10N2·H+ under cold (∼10 K) gas-phase conditions determined the conformation of the C11H10N2 unit of the C11H10N2·H+ cation. This report demonstrates that cold gas-phase UV spectroscopy is a prospectively powerful tool for investigation of the electronic and geometric structures of photochemical intermediates produced in solution.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cb177dca2f440cea413a821826922fd1 https://doi.org/10.1021/acs.jpca.1c04807 Zobrazit plný text záznamu