Generation and spectroscopic identification of selenofulminic acid and its methyl and cyano derivatives (XCNSe, X=H, CH ₃, NC)

Evidence for the existence of nitrile selenides, potential 1,3-dipolarophiles in cycloaddition reactions, has been provided by direct spectroscopic methods. The parent nitrile selenide, selenofulminic acid (HCNSe), and its methyl and cyano derivatives have been photolytically generated in an inert solid argon matrix from 1,2,5-selenadiazoles by 280, 254, and 313 nm UV irradiation, respectively, and studied by ultraviolet spectroscopy and mid-infrared spectroscopy. Ground-state geometries have been obtained from quantum-chemical calculations at the CCSD(T)/aug-cc-pVTZ level. Nitrile selenides are predicted to be linear with a relatively weak N-Se bond. Nitrile selenides (XCNSe, X=H, CH ₃, CN) were photochemically generated in a low-temperature solid argon matrix and studied by UV and IR spectroscopies and quantum chemical calculations.