title: Intramolecular direct C-H arylation approach to fused purines. Synthesis of purino[8,9-f]phenanthridines and 5,6-dihydropurino[8,9-a]isoquinolines.
abstract: Intramolecular C-H arylations were employed as a key step in the synthesis of hitherto unknown fused purine systems: 13-substituted purino[8,9-f]phenanthridines and 11-substituted 5,6-dihydropurino[8,9-a]isoquinolines. The purino[8,9-f]phenanthridines were prepared in moderate yields by double C-H arylations of 9-phenylpurines with 1,2-diiodobenzene or, more efficiently, by consecutive Suzuki coupling of 9-(2-bromophenyl)purines with 2-bromophenylboronic acid followed by intramolecular C-H arylation. 5,6-Dihydropurino[8,9-a]isoquinolines were prepared in quantitative yields by intramolecular C-H arylations of 9-(2-chlorophenethyl)purines.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, CZ-16610, Prague 6, Czech Republic.
authors.forename: Igor
authors.initials: I
authors.lastname: Cerna
authors.forename: Radek
authors.initials: R
authors.lastname: Pohl
authors.forename: Blanka
authors.initials: B
authors.lastname: Klepetárová
authors.forename: Michal
authors.initials: M
authors.lastname: Hocek
mesh_terms: D018360:Crystallography, X-Ray; D003500:Cyclization; D006860:Hydrogen Bonding; D007546:Isoquinolines / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D010617:Phenanthridines / Q000138:chemical synthesis* / Q000737:chemistry; D011687:Purines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D007546:Isoquinolines; D010617:Phenanthridines; D011687:Purines