A Facile Synthesis of Homotriptycenes from Anthranol Derivatives

Derong Cao; Chunmei Gao; Herbert Meier

doi:10.1055/s-2005-921929

LETTER

A Facile Synthesis of Homotriptycenes from Anthranol Derivatives

Derong Cao*^a,b, Chunmei Gao^a,c, Herbert Meier^d
^a LCLC, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650, P. R. of China
^b College of Chemistry, South China University of Technology, Guangzhou 510641, P. R. of China
Fax: +86(20)85232903; e-Mail: caodr@gic.ac.cn;
^c Graduate School of CAS, Beijing 100039, P. R. of China
^d Institute of Organic Chemistry, University of Mainz, 55099 Mainz, Germany

Abstract

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Abstract

Substituted trans-10-benzyl-9-anthranols 5a,b and substituted 10,10-dibenzyl-9-anthranol 8e undergo intramolecular cyclization in the presence of formic or oxalic acid to give homotriptycenes 9a,b,e. Depending on the amount of acid used, a competitive 1,4-dehydration to anthracene derivatives 10a,b was observed for 5a,b. The latter process was the only reaction pathway for anthranols that do not possess electron-donating substituents on benzyl moiety (5c,d → 10c,d).

Key words

aromatization - condensation - electrophilic substitution - transannular ring closure

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References

1a Kottas GS. Clarke LI. Horinek D. Michl J. Chem. Rev. 2005, 105: 128

1b Gung BW. Xue X. Reich HJ. J. Org. Chem. 2005, 70: 3641

1c Godinez CE. Zepeda G. Mortko CJ. Dang H. Garcia-Garibay MA. J. Org. Chem. 2004, 69: 1652

1d Long TM. Swager TM. J. Am. Chem. Soc. 2003, 125: 14113

1e Wiehe A. Senge M. Schäfer OA. Speck M. Tannert S. Kurreck H. Röder B. Tetrahedron 2001, 57: 10089

2a Satrijo A. Swager TM. Macromolecules 2005, 38: 4054

2b Perepichka DF. Bendikov M. Meng H. Wudl F. J. Am. Chem. Soc. 2003, 125: 10190

2c Beyeler A. Belser P. Coord. Chem. Rev. 2002, 230: 28

2d Korth O. Wiehe A. Kurreck H. Röder B. Chem. Phys. 1999, 246: 363

2e Norvez S. Barzoukas M. Chem. Phys. Lett. 1990, 16: 41

3a Xanthopoulou NJ. Kourounakis AP. Spyroudis S. Kourounakis PN. Eur. J. Med. Chem. 2003, 621

3b Perchellet EM. Sperfslage BJ. Wang Y. Huang X. Tamura M. Hua DH. Perchellet JP. Anti-Cancer Drugs 2002, 13: 567

3c Yang W. Perchellet EM. Tamura M. Hua DH. Perchellet JP. Cancer Lett. 2002, 18: 73

4a Kinbara K. Aida T. Chem. Rev. 2005, 105: 1377

4b Wolpaw AJ. Aizer AA. Zimmt MB. Tetrahedron Lett. 2003, 44: 7613

4c Zhu Z. Swager TM. J. Am. Chem. Soc. 2002, 124: 9670

4d Hashimoto M. Yamamura K. Yamane J. Tetrahedron 2001, 57: 10253

4e Müller T. Hulliger J. Seichter W. Weber E. Weber T. Wübbenhorst M. Acc. Chem. Res. 2001, 34: 514

5 Cristol SJ. Pennelle DX. J. Org. Chem. 1970, 35: 2357

6 Baumgart KD. Harnish H. Seebach US. Szeimies G. Chem. Ber. 1985, 110: 2883

7 Saito K. Ito K. Takahashi K. Kagabu S. Org. Prep. Proced. Int. 1991, 23: 196

See:

8a Prinz H. Ishii Y. Hirano T. Stoiber T. Gomez JAC. Schmidt P. Duessmann H. Burger AM. Prehn JHM. Guenther EG. Unger E. Umezawa K. J. Med. Chem. 2003, 46: 3382

8b Hu WX. Zhu W. Bioorg. Med. Chem. Lett. 2004, 14: 621

9

As experimental example, the synthesis of 3,5-dimethoxypentacyclo [7.6.6.0^2,7.0^10,15.0^16,17] heneicosa-2,4,6,10,12,14,16,18,20-nonaene (9a) is described here. Compound 3a (342 mg, 1.00 mmol) was hydrogenated overnight at ambient temperature in 18 mL EtOAc and 6 mL MeOH in the presence of 5% Pd/C (380 mg). The mixture was filtered through silica gel and the volatile parts removed in vacuo. The residue was dissolved in 4 mL diglyme and treated for 30 min with NaBH₄ (120 mg, 3.17 mmol), before 2 mL MeOH were added dropwise. After further 10 min stirring, 60 mg (1.59 mmol) NaBH₄ was added and the reaction mixture stirred at r.t. overnight. All these procedures after the reaction with H₂ were performed in a N₂ atmosphere. Dropwise addition of oxalic acid led to pH 2. After 1 h stirring H₂O was slowly added. A solid precipitated which was purified by column chromatography [30 × 3 cm SiO₂, PE (bp 40-70 °C)-EtOAc, 30:1]. Colorless crystals of 9a (222 mg, 68% total yield related to 3a) were obtained which melted at 165 °C. ¹H NMR (300 MHz, CDCl₃): δ = 3.21 (d, ³ J = 2.6 Hz, 2 H, 8-H), 3.63 (s, 3 H, OCH₃), 3.89 (s, 3 H, OCH₃), 4.19 (t, ³ J = 2.6 Hz, 1 H, 9-H), 5.69 (s, 1 H, 1-H), 6.00 (d, ⁴ J = 1.8 Hz, 1 H, 4-H), 6.22 (d, ⁴ J = 1.8 Hz, 1 H, 6-H), 7.09-7.14 (m, 4 H, aromat. H), 7.31-7.35 (m, 4 H, aromat. H). ¹³C NMR (75 MHz, CDCl₃): δ = 37.4, 41.9, 45.6, 55.1, 56.1, 96.6, 107.5, 125.1, 125.6, 126.2, 126.2, 141.1, 144.7, 123.0, 136.7, 156.4, 158.5. FD-MS: m/z (%) = 328 (100) [M⁺]. Anal. Calcd for C₂₃H₂₀O₂ (328.4): C, 84.12; H, 6.14. Found: C, 84.15; H, 6.17. Structure of 9a could be additionally established by a crystal structure analysis, which shall be published later.

10a Landucci LL. Ralph J. J. Org. Chem. 1982, 47: 3486

10b Ralph J. Landucci LL. J. Org. Chem. 1983, 48: 372