title: Dehydroaromatization of quinoxalines: one-step syntheses of trinuclear 1,6,7,12,13,18-hexaazatrinaphthylene titanium complexes.
abstract: We report the spontaneous coupling of N-heterocycles, initiated by C-H bond activation reactions. The reaction of quinoxalines and the titanocene acetylene complex Cp2Ti{eta2-C2(SiMe3)2}, as an excellent titanocene source, results in the formation of trinuclear 1,6,7,12,13,18-hexaazatrinaphthylene (HATN) titanium complexes. These HATN titanium complexes are thermally stable but sensitive to air and moisture. A three-fold dehydrogenative C-C coupling is proposed as the main step in the presented synthetic procedure. Particularly using commercial starting materials, an efficient route for the dehydrogenative coupling of N-heterocycles, leading to multidentate ligands, has been established.
authors.affiliation: Institute of Pure and Applied Chemistry, University of Oldenburg, D-26111 Oldenburg, Germany.
authors.forename: Ingmar M
authors.initials: IM
authors.lastname: Piglosiewicz
authors.forename: Ruediger
authors.initials: R
authors.lastname: Beckhaus
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Saak
authors.forename: Detlev
authors.initials: D
authors.lastname: Haase
mesh_terms: D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D011810:Quinoxalines / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: C507193:1,6,7,12,13,18-hexaazatrinaphthylene titanium; D009942:Organometallic Compounds; D011810:Quinoxalines; D014025:Titanium