Matrix isolation photochemistry: photoequilibrium between transient o-benzyne, carbon monoxide and transient cyclopentadienylideneketene in an argon matrix

Photolysis of a Benzyne Precursor Studied by Time-Resolved FTIR Spectroscopy

“…However, it is important to point out that [3 + 2] cycloadditions between 1 and azides have been conducted via photolysis of 2 in dichloroethane solvent at room temperature . Conducting the photolysis of 2 in CO-saturated acetonitrile gives rise to experimental data that is identical to that obtained when experiments are carried out in Ar atmosphere, thus confirming that a reaction between 1 and CO giving rise to benzocyclopropenone requires activation …”

“…16 Conducting the photolysis of 2 in CO-saturated acetonitrile gives rise to experimental data that is identical to that obtained when experiments are carried out in Ar atmosphere, thus confirming that a reaction between 1 and CO giving rise to benzocyclopropenone requires activation. 37 Inspired by the quenching experiment on 1 with furan at 50 K in an argon matrix by Chapman, 22 I decided to use the Diels−Alder reactivity of 1 as a probe of its presence. For enhancement of the IR sensitivity of the corresponding Diels− Alder reaction, methyl 1-methylpyrrole-2-carboxylate (6) was selected.…”

Direct observation ofo-benzyne formation in photochemical hexadehydro-Diels–Alder (hν-HDDA) reactions

“…There are only few investigations of electronic absorption spectra in the ultraviolet/ visible (UV/VIS) range, in the gas phase or in low-temperature matrices. [76][77][78][79][80][81][82] To the best of our knowledge, the electronic absorption spectrum, i.e., the UV/VIS spectrum, of o-benzyne in solution, has not been reported.…”

Reactions Inside Carcerands

“…14,47 Since its discovery, 48 -49 o -benzyne has received 50 and due to its interesting structural and electronic properties. 51,52 Benzyne has been investigated in cryogenic matrices by UV/Vis -, 53 FT -IR -, 54,55 and very recently solid state NMR spectroscopy. 56 Chapman fi rst matrix -isolated o -benzyne by photolyzing benzocyclobutenedione 29 at 8 K (Figure 9.20 ).…”