Photochemistry of Tris(2,4-dibromophenyl)amine and its Application to Co-oxidation on Sulfides and Phosphines

Sergio M Bonesi; Mariella Mella; Daniele Merli; Stefano Protti

doi:10.1111/php.13403

Photochemistry of Tris(2,4-dibromophenyl)amine and its Application to Co-oxidation on Sulfides and Phosphines

Photochem Photobiol. 2021 Nov;97(6):1278-1288. doi: 10.1111/php.13403. Epub 2021 Mar 8.

Authors

Sergio M Bonesi^{1

2

3}, Mariella Mella⁴, Daniele Merli⁴, Stefano Protti³

Affiliations

¹ Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
² Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina.
³ PhotoGreen Lab, Department of Chemistry, University of Pavia, Pavia, Italy.
⁴ Department of Chemistry, University of Pavia, Pavia, Italy.

PMID: 33609291
DOI: 10.1111/php.13403

Abstract

The photochemistry of tris(2,4-dibromophenyl)amine was investigated via time-resolved nanosecond spectroscopy. The tris(2,4-dibromophenyl)amine radical cation ("Magic Green") was immediately detected after the laser pulse; this intermediate then cyclizes to N-aryl-4a,4b-dihydrocarbazole radical cation. The latter transient reacted with molecular oxygen to provide the corresponding hydroperoxyl radical, which smoothly co-oxidize sulfides into sulfoxides. On the other hand, the photogenerated "Magic Green" was exploited to promote the co-oxidation of nucleophilic triarylphosphines to triarylphosphine oxides through an electron transfer process preventing the amine cyclization. In this case, the intermediate Ar₃ POO^•+ was found to play a key role in phosphine oxide formation.

Publication types

Review