Bonesi Sergio M, Protti Stefano, Albini Angelo
Departamento de Química Orgánica, CIHIDECAR-CONICET, 3er Piso, Pabellón 2, Ciudad Universitaria, FCEyN , University of Buenos Aires , Buenos Aires 1428 , Argentina.
PhotoGreen Lab, Department of Chemistry , University of Pavia , V. leTaramelli 12 , 27100 Pavia , Italy.
J Org Chem. 2018 Aug 3;83(15):8104-8113. doi: 10.1021/acs.joc.8b00913. Epub 2018 Jun 12.
The photochemistry of tris( p-bromophenyl)amine was investigated in a nitrogen- and oxygen-flushed solution under laser flash photolysis conditions. The detected intermediates were the corresponding amine radical cation ("Magic Blue") and the N-phenyl-4a,4b-dihydrocarbazole radical cation that, under an oxygen atmosphere, is converted to the corresponding hydroperoxyl radical. The role of the last species was supported by the smooth co-oxidation of sulfides to sulfoxides. On the other hand, co-oxidation of nucleophilic triarylphosphines to triarylphosphine oxides arose from an electron transfer between the photogenerated "Magic Blue" and phosphine that prevented the amine cyclization. In this case, intermediate ArPOO was found to play a key role in phosphine oxide formation.
在激光闪光光解条件下，对三（对溴苯基）胺在氮气和氧气吹扫的溶液中的光化学进行了研究。检测到的中间体是相应的胺自由基阳离子（“魔蓝”）和N-苯基-4a,4b-二氢咔唑自由基阳离子，在氧气气氛下，该阳离子会转化为相应的氢过氧自由基。硫化物平稳地共氧化为亚砜，这支持了最后一种物质的作用。另一方面，亲核三芳基膦共氧化为三芳基氧化膦是由光生“魔蓝”与膦之间的电子转移引起的，该电子转移阻止了胺环化。在这种情况下，发现中间体ArPOO在氧化膦形成中起关键作用。
