Research in the chemistry of phenoxazines

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

“…In previous studies on the coupling of 3 H -phenoxazin-3-one derivatives 8 and 9 with o -phenylenediamine [ 10 – 11 ], the preference was given to the 12 Н -quinoxaline[2,3- b ]phenoxazine form 7 ( Scheme 5 ). A series of N -aryl derivatives of this form was also obtained via treatment of 6,8-di- tert -butyl- N -aryl-3 H -phenoxazin-3-imines with various arylamines in the presence of an excess of trifluoroacetic acid [ 9 ].…”

“… Preparation of quinoxaline[2,3- b ]phenoxazine ( 7 ) from 2-amino-3 H -phenoxazin-3-one ( 8 ) [ 10 ] and 2-ethoxy-3 H -phenoxazin-3-one ( 9 ) [ 11 ], respectively. …”

“…Using o -amino-, o -hydroxy- and o -mercapto-substituted anilines in this process allowed to pursue both principal reaction pathways (Schiff base formation and S N H), which led to the formation of derivatives of the previously unknown 14 Н -quinoxaline[2,3- b ]phenoxazine system 5 ( Scheme 3 ) as well as N,O- and N,S-heteropentacyclic triphenodioxazines and oxazinophenothiazine 10a – c . The structural assignment [ 10 – 11 ] of the N,O-containing reaction products as 12 H -quinoxaline[2,3- b ]phenoxazines was confirmed through DFT calculations, X-ray crystallography, and NMR spectroscopy.…”

Dermacozine N, the First Natural Linear Pentacyclic Oxazinophenazine with UV–Vis Absorption Maxima in the Near Infrared Region, along with Dermacozines O and P Isolated from the Mariana Trench Sediment Strain Dermacoccus abyssi MT 1.1T

“…In 1978, G.B. Afanas'eva et al reported the synthesis of the same oxazinophenazine skeleton when they carried out nucleophilic substitution of 2-ethoxy-3-phenoxazinone with ortho-phenylendiamine [29]. Given the compound absorption maxima of 1 in the near infrared spectrum (NIR), its fluorescence spectroscopic investigation would be intriguing in the future.…”

Facile Approach to the N,O,S-Heteropentacycles via Condensation of Sterically Crowded 3H-Phenoxazin-3-one with ortho-amino-, hydroxy- and mercaptoanilines

“…1) 3H-phenoxazin-3-ones easily accessed through the oxidation couplings of oaminophenols [3,4] or N-aryl-o-benzoquinone imines [5,6] can serve as efficient precursors to pentacyclic N, O-heterocyclic compounds possessing promising properties for application in fluorescent probe, organic light-emitting diode and organic solar cells devices [2,[7][8][9]. The principal way to the formation of these compounds is the nucleophilic addition of aromatic amines to 3H-phenoxazin-3-ones and the subsequent cyclization of the initially formed adducts [10][11][12]. Reactivity of 3Hphenoxazin-3-ones is primarily determined by the properties of its p-quinone imine moiety.…”