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Synlett 2013; 24(5): 615-618
DOI: 10.1055/s-0032-1318310
letter
© Georg Thieme Verlag Stuttgart · New York

Total Synthesis of (±)-Spirobenzofuran

Hang Su
a   Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610 064, P. R. of China   Fax: +86(28)85413712   Email: chembliu@scu.edu.cn
,
Ting Zhou
a   Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610 064, P. R. of China   Fax: +86(28)85413712   Email: chembliu@scu.edu.cn
,
Bo Liu*
a   Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610 064, P. R. of China   Fax: +86(28)85413712   Email: chembliu@scu.edu.cn
b   Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, 345 Lingling Road, Shanghai 200 032, P. R. of China
› Author Affiliations
Further Information

Publication History

Received: 12 January 2013

Accepted after revision: 04 February 2013

Publication Date:
20 February 2013 (online)

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Abstract

Spirobenzofuran, embracing a cyclopentane-spirofused benzofuran carbon framework, was efficiently assembled via semipinacol rearrangement with Me3Al from 2,5-dimethoxy-4-methylacetophenone.

Key words

spirobenzofuran - semipinacol rearrangement - trimethylaluminium - total synthesis - sesquiterpenoid

Supporting Information

    for this article is available online at http://www.thieme-connect.com/ejournals/toc/synlett.
  • Supporting Information
 

  • References

  • 1 Kleinwachter P, Schlegel B, Dorfelt H, Gräfe U. J. Antibiot. 2001; 54: 526
    CrossrefSearch in Google Scholar
  • 3 Asakawa Y, Kondo K, Tori M. Phytochemistry 1991; 30: 325
    CrossrefSearch in Google Scholar
  • 4 Toyota M, Koyama H, Asakawa Y. Phytochemistry 1997; 46: 145
    CrossrefSearch in Google Scholar
  • 5 Natori S, Inouye Y, Nishikawa H. Chem. Pharm. Bull. 1967; 15: 380
    CrossrefSearch in Google Scholar
  • 7 Srikrishna A, Lakshmi BV. Tetrahedron Lett. 2005; 46: 7029
    CrossrefSearch in Google Scholar
  • 8 Fuganti C, Serra S. J. Chem. Soc., Perkin Trans. 1 2000; 3758
  • 10 Lukas RJ, Muresan AZ, Damaj MI, Blough BE, Huang X.-D, Navarro HA, Mascarella SW, Eaton JB, Marxer-Miller SK, Carroll FI. J. Med. Chem. 2010; 53: 4731
    CrossrefSearch in Google Scholar
  • 11 Danishefsky S, Etheredge SJ. J. Org. Chem. 1982; 47: 4791
    CrossrefSearch in Google Scholar
  • 12 Payette JN, Honda T, Yoshizawa H, Favaloro FG. Jr, Gribble GW. J. Org. Chem. 2006; 71: 416
    CrossrefSearch in Google Scholar
  • 13 Cleve A, Fritzemeier K.-H, Heinrich N, Klar U, Müller-Fahrnow A, Neef G, Ottow E, Schwede W. Tetrahedron 1996; 52: 1529
    CrossrefSearch in Google Scholar
  • 14 Analytical Data 1H NMR (400 MHz, CDCl3): δ = 6.86 (s, 1 H), 6.67 (s, 1 H), 3.93–3.84 (m, 4 H), 3.79 (s, 3 H), 3.77 (s, 3 H), 2.78 (s, 1 H), 2.37 (d, J = 15.2 Hz, A of AB, 1 H), 2.23 (d, J = 16.0 Hz, B of AB, 1 H), 2.20 (s, 3 H), 1.65 (d, J = 13.6 Hz, A′ of A′B′, 1 H), 1.42 (d, J = 13.6 Hz, B′ of A′B′ 1 H), 1.24 (s, 3 H), 1.15 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 151.6, 150.1, 128.4, 126.6, 114.1, 109.5, 108.2, 68.2, 64.0, 63.9, 61.1, 56.1, 56.0, 41.2, 39.2, 32.0, 27.9, 26.2, 16.4. IR (thin film): 2955, 1506, 1296, 1093, 823 cm–1.
  • 17 Kita Y, Yoshida Y, Mihara S, Furukawa A, Higuchi K, Fang DF, Fujioka H. Tetrahedron 1998; 54: 14689
    CrossrefSearch in Google Scholar
  • 18 Synthesis of Aldehyde 5 To a solution of compound 6 (200 mg, 0.59 mmol) in CH2Cl2 (10 mL) was added Me3Al (0.59 mL, 1.18 mol, 2.0 M in toluene) dropwise at –10 °C under argon. The reaction was warmed to r.t. slowly and stirred for 4 h. Then it was quenched with sat. aq NaHCO3 (2 mL) at 0 °C. Sat. aq sodium potassium tartrate (10 mL) was added, and the biphasic mixture was stirred overnight. The aqueous layer was separated and extracted with CH2Cl2 (3 × 5 mL). The residue was purified by flash chromatography (silica gel, PE–EtOAc = 10:1) to give compound 5 as a yellow solid (176 mg, 88%).1H NMR (400 MHz, CDCl3): δ = 9.87 (s, 1 H), 6.92 (s, 1 H), 6.69 (s, 1 H), 3.93–3.88 (m, 4 H), 3.79 (s, 3 H), 3.67 (s, 3 H), 2.77 (d, J = 15.2 Hz, A of AB, 1 H), 2.31 (d, J = 15.2 Hz, B of AB, 1 H), 2.27 (d, J = 14.0 Hz, A′ of A′B′, 1 H), 2.20 (s, 3 H), 1.99 (d, J = 13.6 Hz, B′of A′B′, 1 H), 1.27 (s, 3 H), 0.83 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 201.8, 151.8, 150.7, 127.0, 125.8, 114.8, 114.8, 112.3, 64.3, 64.3, 63.3, 56.3, 55.9, 51.9, 44.2, 43.8, 27.0, 23.9, 16.2. IR (thin film): 2959, 1716, 1213, 858 cm–1.
  • 19 Keiji M, Takashi O, Hisashi Y. J. Am. Chem. Soc. 1989; 111: 6431
    CrossrefSearch in Google Scholar
  • 20 Kingsbury JS, Corey EJ. J. Am. Chem. Soc. 2005; 127: 13813
    CrossrefSearch in Google Scholar
  • 22 Kostikov AP, Popik VV. J. Org. Chem. 2007; 72: 9190
    CrossrefSearch in Google Scholar
  • 23 Analytical Data 1H NMR (400 MHz, DMSO-d 6): δ = 8.66 (s, 1 H), 7.14 (d, J = 5.6 Hz, 1 H), 6.52 (s, 2 H), 5.79 (d, J = 5.6 Hz, 1 H), 2.83 (d, J = 18.8 Hz, A of AB, 1 H), 2.44 (d, J = 18.8 Hz, B of AB, 1 H), 2.34 (d, J = 18.4 Hz, A′ of A′B′, 1 H), 2.24 (d, J = 18.0 Hz, B′ of A′B′, 1 H), 2.07 (s, 3 H), 0.98 (s, 3 H), 0.85 (s, 3 H). 13C NMR (100 MHz, DMSO-d 6): δ = 216.2, 150.3, 148.9, 126.5, 123.8, 111.2, 111.0, 102.1, 59.2, 51.9, 42.7, 41.2, 24.6, 23.0, 16.3. IR (thin film): 3395, 1732, 1412, 1085, 923 cm–1. HRMS (ES+): m/z calcd for C15H18O4Na [M + Na]+: 285.1103; found: 285.1101.