Synthesis, structure, and properties of a dibenzo-ortho-terphenoquinone. The first o-terphenoquinone derivative

Chemistry Letters

Volumn 32, Issue 6, 2003, Pages 538-539

  Kurata, Hiroyuki ^a   Takehara, Yuko ^a   Kawase, Takeshi ^a   Oda, Masaji ^a  

^a OSAKA UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

DIBENZO 2 TERPENOQUINONE; EXOCYCLIC DOUBLE BOND; QUINONE DERIVATIVE; RADICAL; TERPHENYL DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL ANALYSIS; CHEMICAL STRUCTURE; ELECTRON SPIN RESONANCE; ISOMER; ROTATION; SYNTHESIS;

EID: 0041760416     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.2003.538     Document Type: Article

References (15)

1. For reviews; a) "The Chemistry of Quinonoid Compounds," ed. by S. Patai, Wiley, London (1974). b) "The Chemistry of Quinonoid Compounds Vol. II," ed. by S. Patai and Z. Rappoport, Wiley, Chichester (1988).
2. For reviews; a) "The Chemistry of Quinonoid Compounds," ed. by S. Patai, Wiley, London (1974). b) "The Chemistry of Quinonoid Compounds Vol. II," ed. by S. Patai and Z. Rappoport, Wiley, Chichester (1988).
3. a) R. West, J. A. Jorgenson, K. L. Steariy, and J. C. Calabrese, J. Chem. Soc., Chem. Commun., 1991, 1234.
4. b) P. Boldt, D. Bruhnke, F. Gerson, M. Scholz, P. G. Jones, and F. Bär, Helv. Chim. Acta, 76, 1739 (1993).
5. c) A. Rebmann, J. Zhou, P. Schuler, H. B. Stegmann, and A. Rieker, J. Chem. Res., Synop., 1996, 318.
6. H. Kurata, T. Tanaka, and M. Oda, Chem. Lett., 1999, 749.
7. H. Kurata, T. Tanaka, T. Sauchi, T. Kawase, and M. Oda, Chem. Lett., 1997, 947.
8. We tentatively assign the trans configuration for 3 from the viewpoint of steric hindrance on the second nucleophilic addition of the dianion.
9. For similar way for the synthesis of 9,10-disubstituted phenanthrenes, see; Y.-H. Lai, J. Chem. Soc., Perkin Trans. 2, 1986, 1667.
10. 2: C, 86.26, H, 8.27%.
11. The thermal equilibrium with the diradical form may be responsible for the easy rotation of the pinch bonds.
12. int = 0.094) used in refinement. R1 = 0.059 (7835 data, I > 2σ(I)), wR = 0.140 (all data), T = 203 K. CCDC 206981.
13. 2, sweep rate 100 mV/s, ferrocene = +0.32 V, 25°C.
14. 1H NMR signals of 2 are observed normally indicates very low concentration of diradical 2B.
15. Photoirradiation of 2 gave rise to weak ESR signals other than the triplet pattern that also disappear in the dark to suggest occurrence of a reversible side reaction. There seems a possibility of electro-cyclization of the bisquinomethylenethane moiety with some similarity to the photochemical cyclization of cis-stilbene, and further studies on this point are underway.