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Synlett 2014; 25(16): 2355-2359
DOI: 10.1055/s-0034-1378581
letter
© Georg Thieme Verlag Stuttgart · New York

Type 2 Ring-Opening Reactions of Cyclopropanated 7-Oxabenzonorbornadienes under Acid Catalysis

Andrew Tigchelaar
Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada   Fax: +1(519)7661499   Email: wtam@uoguelph.ca
,
Jamie Haner
Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada   Fax: +1(519)7661499   Email: wtam@uoguelph.ca
,
Emily Carlson
Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada   Fax: +1(519)7661499   Email: wtam@uoguelph.ca
,
William Tam*
Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada   Fax: +1(519)7661499   Email: wtam@uoguelph.ca
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Further Information

Publication History

Received: 27 March 2014

Accepted after revision: 11 July 2014

Publication Date:
06 August 2014 (online)

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Abstract

A novel ring-opening mode of cyclopropanated 7-oxa­benzonorbornadiene under acid catalysis has been discovered, providing various 2-(alkoxymethyl)naphthalenes through the use of alcohol nucleophiles. The reaction was most effective with catalytic p-TsOH∙H2O in methanol, offering yields up to 91%. The compatibility of secondary and tertiary alcohols, as well as functionalized substrates was also demonstrated.

Key words

fused-ring systems - cyclopropane - ring-opening reactions - regioselectivity - acid catalysis

Supporting Information

    for this article is available online at http://www.thieme-connect.com/products/ejournals/journal/ 10.1055/s-00000083.
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  • References and Notes

  • 1 Bournaud C, Chung F, Luna AP, Pasco M, Errasti G, Lecourt T, Micouin L. Synthesis 2009; 869
    Thieme Connect
  • 2 Tam W, Cockburn N. Synlett 2010; 1170
    Thieme Connect
  • 3 Rayabarapu DK, Cheng C.-H. Acc. Chem. Res. 2007; 40: 971
    CrossrefPubMedSearch in Google Scholar
  • 4 Lautens M, Fagnou K, Heibert S. Acc. Chem. Res. 2003; 36: 48
    CrossrefPubMedSearch in Google Scholar
  • 5 Woo S, Keay BA. Synthesis 1996; 669
    Thieme Connect
  • 6 Chiu P, Lautens M. Top. Curr. Chem. 1997; 190: 1
    Search in Google Scholar
  • 7 Lautens M, Dockendorff C, Fagnou K, Malicki A. Org. Lett. 2002; 4: 1311
    CrossrefPubMedSearch in Google Scholar
  • 8 Lautens M, Dockendorff C. Org. Lett. 2003; 5: 3695
    CrossrefSearch in Google Scholar
  • 9 Duan J, Cheng C.-H. Tetrahedron Lett. 1993; 34: 4019
    CrossrefSearch in Google Scholar
  • 10 Feng C, Nandi TS, Cheng C.-H. J. Org. Chem. 1999; 64: 3538
    CrossrefPubMedSearch in Google Scholar
  • 11 Lautens M, Hiebert S. J. Am. Chem. Soc. 2004; 126: 1437
    CrossrefSearch in Google Scholar
  • 12 Wu MS, Jeganmohan M, Cheng C.-H. J. Org. Chem. 2005; 70: 9545
    CrossrefPubMedSearch in Google Scholar
  • 13 Leong P, Lautens M. J. Org. Chem. 2004; 69: 2194
    CrossrefPubMedSearch in Google Scholar
  • 14 Bertozzi F, Pineschi M, Macchia F, Arnold LA, Minnaard AJ, Feringa BL. Org. Lett. 2002; 4: 2703
    CrossrefPubMedSearch in Google Scholar
  • 15 Fan E, Shi W, Lowary TL. J. Org. Chem. 2007; 72: 2917
    CrossrefSearch in Google Scholar
  • 16 Madan S, Cheng C.-H. J. Org. Chem. 2006; 71: 8312
    CrossrefSearch in Google Scholar
  • 17 Lautens M, Rovis T. Tetrahedron 1999; 55: 8967
    CrossrefSearch in Google Scholar
  • 18 de Meijere A. Angew. Chem. Int. Ed. Engl. 1979; 18: 809
    Search in Google Scholar
  • 19 McKee M, Haner J, Carlson E, Tam W. Synthesis 2014; 46: 1518
    Thieme ConnectSearch in Google Scholar
  • 20 Frejaville C, Jullien R. Tetrahedron Lett. 1971; 23: 2039
    Search in Google Scholar
  • 21 Bertz SH, Dabbagh G, Cook JM, Honkan V. J. Org. Chem. 1984; 49: 1739
    CrossrefSearch in Google Scholar
  • 22 Hughes S, Griffiths G, Stirling CJ. M. J. Chem. Soc., Perkin Trans. 2 1987; 1253
  • 23 Carlson E, Haner J, McKee M, Tam W. Org. Lett. 2014; 16: 1776
    CrossrefSearch in Google Scholar
  • 24 Guan B.-T, Xiang S.-K, Wang B.-Q, Sun Z.-P, Wang Y, Zhao K.-Q, Shi Z.-J. J. Am. Chem. Soc. 2008; 130: 3268
    CrossrefSearch in Google Scholar
  • 25 Nakata D, Sakuma T, Kono K, Sato S, Tani S, Kunishima M. Chem. Pharm. Bull. 2001; 49: 97
    CrossrefSearch in Google Scholar
  • 26 Ahern C, Darcy R. Synth. Commun. 1998; 28: 971
    CrossrefSearch in Google Scholar
  • 27 Halton B, Kay AJ, Zhi-mei Z, Boese R, Haumann T. J. Chem. Soc., Perkin Trans. 1 1996; 1445
  • 28 Scott K, Stonehouse J, Keeler J, Hwang T.-L, Shaka AJ. J. Am. Chem. Soc. 1995; 117: 4199
    CrossrefSearch in Google Scholar
  • 29 Shibata T, Ueno Y, Kanda K. Synlett 2006; 411
  • 30 Engler TA, Shechter H. J. Org. Chem. 1999; 64: 4247
    CrossrefSearch in Google Scholar
  • 31 Hughes TS, Carpenter BK. J. Chem. Soc., Perkin Trans. 2 1999; 2291
  • 32 Myers AG. Tetrahedron Lett. 1987; 28: 4493
    CrossrefSearch in Google Scholar
  • 33 Álvarez-Bercedo P, Martin R. J. Am. Chem. Soc. 2010; 132: 17352
    CrossrefSearch in Google Scholar
  • 34 General Procedure: In a small screw-cap vial containing a stir-bar, cyclopropanated oxabenzonorbornadiene 2 (1.0 equiv.) was dissolved in alcohol (0.5 mL). The reaction was cooled to 0 °C, and PTSA (0.1 equiv.) was added as a solid. The reaction was stirred at 0 °C for 10 min, then slowly warmed to r.t. The vial was sealed and secured tightly with polytetrafluoroethylene (PTFE) thread-seal tape and paraffin film, and heated to 90 or 110 °C with continuous stirring for 24–330 h. The crude product was directly loaded onto a chromatography column and purified (EtOAc–hexanes). 2-(Methoxymethyl)naphthalene (6a; Table 2, entry 1): Yield: 34.3 mg (82%); clear oil; Rf = 0.33 (EtOAc–hexanes, 1:9). 1H NMR (400 MHz, CDCl3): δ = 7.82–7.84 (m, 3 H), 7.78 (s, 1 H), 7.45–7.48 (m, 3 H), 4.62 (s, 2 H), 3.43 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 135.7, 133.3, 133.0, 128.2, 127.9, 127.7, 126.5, 126.1, 125.9, 125.7, 74.8, 58.2. Spectral data are consistent with those previously reported.24 2-(Ethoxymethyl)naphthalene (6b; Table 2, entry 2): Yield: 25.3 mg (77%); clear oil; Rf = 0.40 (EtOAc–hexanes, 1:9). 1H NMR (400 MHz, CDCl3): δ = 7.80–7.82 (m, 3 H), 7.77 (s, 1 H), 7.44–7.47 (m, 3 H), 4.66 (s, 2 H), 3.57 (q, J = 7.0 Hz, 2 H), 1.26 (t, J = 7.0 Hz, 3 H). 13C NMR (100 MHz, CDCl3): δ = 136.1, 133.3, 133.0, 128.1, 127.9, 127.7, 126.3, 126.0, 125.8, 125.7, 72.8, 65.8, 15.3. Spectral data are consistent with those previously reported.24 2-(Butoxymethyl)naphthalene (6c; Table 2, entry 3 ): Yield: 37.1 mg (61%); clear oil; Rf = 0.40 (EtOAc–hexanes, 1:9). IR (neat): 3055 (s), 2958 (s), 2932 (s), 2869 (s), 1603 (m), 1509 (s), 1464 (s), 1374 (s), 1170 (m), 1098 (s), 854 (s), 816 (s), 751 (s) cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.80–7.82 (m, 3 H), 7.76 (s, 1 H), 7.43–7.47 (m, 3 H), 4.65 (s, 2 H), 3.50 (t, J = 6.6 Hz, 2 H), 1.62 (m, 2 H), 1.40 (m, 2 H), 0.91 (t, J = 7.3 Hz, 3 H). 13C NMR (100 MHz, CDCl3): δ = 136.3, 133.3, 133.0, 128.1, 127.9, 127.7, 126.3, 126.0, 125.8, 125.7, 73.0, 70.3, 31.9, 19.4, 14.0. HRMS: m/z [M]+ calcd. for C15H18O: 214.1358; found: 214.1364. Spectral data are consistent with those previously reported.25 2-(Isopropoxymethyl)naphthalene (6d; Table 2, entry 5): Yield: 33.9 mg (67%); clear oil; Rf = 0.41 (EtOAc–hexanes, 1:9). IR (neat): 3055 (m), 2971 (s), 2930 (m), 2868 (m), 2242 (w), 1950 (w), 1726 (w), 1602 (m), 1509 (m), 1467 (m), 1369 (s), 1329 (s), 1124 (s), 1070 (s), 909 (m), 855 (m), 814 (s), 734 (s) cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.79–7.83 (m, 4 H), 7.44–7.49 (m, 3 H), 4.67 (s, 2 H), 3.73 (m, 1 H), 1.23 (d, J = 6.0 Hz, 6 H). 13C NMR (100 MHz, CDCl3): δ = 136.7, 133.4, 132.9, 128.1, 127.9, 127.7, 126.1, 126.0, 125.8, 125.7, 71.0, 70.2, 22.2. HRMS: m/z [M]+ calcd. for C14H16O: 200.1201; found: 200.1205. 2-(Cyclohexoxymethyl)naphthalene (6e; Table 2, entry 6): Yield: 39.3 mg (67%); clear oil; Rf = 0.44 (EtOAc–hexanes, 1:9). IR (neat): 3055 (s), 2930 (s), 2855 (s), 1602 (m), 1509 (s), 1450 (s), 1366 (s), 1090 (s), 854 (m), 816 (s), 734 (s) cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.79–7.83 (m, 4 H), 7.44–7.49 (m, 3 H), 4.71 (s, 2 H), 3.40 (m, 1 H), 2.00 (m, 2 H), 1.76 (m, 2 H), 1.54 (m, 1 H), 1.39 (m, 2 H), 1.25 (m, 3 H). 13C NMR (100 MHz, CDCl3): δ = 136.9, 133.4, 132.9, 128.0, 127.9, 127.7, 126.0, 125.9, 125.8, 125.7, 77.0, 69.8, 32.3, 25.9, 24.2. HRMS: m/z [M]+ calcd. for C17H20O: 240.1514; found: 240.1522. Spectral data are consistent with those previously reported.26 2-(tert-Butoxymethyl)naphthalene (6f; Table 2, entry 7): Yield: 7.1 mg (11%); clear oil; Rf = 0.40 (EtOAc–hexanes, 1:9). 1H NMR (400 MHz, CDCl3): δ = 7.77–7.84 (m, 4 H), 7.39–7.48 (m, 3 H), 4.59 (s, 2 H), 1.32 (s, 9 H). 13C NMR (100 MHz, CDCl3): δ = 137.4, 133.5, 132.8, 128.0, 127.9, 127.8, 127.6, 125.9, 125.8, 125.5, 73.6, 64.3, 27.8. Spectral data are consistent with those previously reported.24 1,4-Dimethoxy-6-(methoxymethyl)naphthalene (6g; Table 3, entry 2): Yield: 18.9 mg (56%); clear oil; Rf = 0.29 (EtOAc–hexanes, 1:9). IR (KBr): 3076 (w), 2996 (m), 2934 (s), 2833 (s), 1633 (w), 1604 (s), 1463 (s), 1361 (w), 1271 (s), 1246 (m), 1095 (s), 804 (s) cm–1. 1H NMR (600 MHz, CDCl3): δ = 8.18 (d, J = 8.6 Hz, 1 H), 8.13 (s, 1 H), 7.49 (dd, J = 8.6, 1.4 Hz, 1 H), 6.68 (ABq, J AB = 8.4 Hz, ΔδAB = 8.8 Hz, 2 H), 4.62 (s, 2 H), 3.941 (s, 3 H), 3.937 (s, 3 H), 3.39 (s, 3 H). 13C NMR (125 MHz, CDCl3): δ = 149.5, 135.7, 126.1, 125.8, 125.6, 122.2, 120.6, 103.4, 103.2, 74.9, 58.0, 55.7. HRMS: m/z [M]+ calcd. for C14H16O3: 232.1099; found: 232.1106. Spectral data are consistent with those previously reported.27 2,3-Dibromo-6-(methoxymethyl)naphthalene (6h; Table 3, entry 3): Yield: 12.8 mg (20%); red solid; mp 40–42 °C; Rf = 0.38 (EtOAc–hexanes, 1:9). IR (KBr): 3058 (w), 2989 (m), 2926 (s), 2884 (m), 2851 (m), 1582 (m), 1453 (m), 1102 (s), 903 (s), 888 (s), 821 (m) cm–1. 1H NMR (600 MHz, CDCl3): δ = 8.11 (s, 1 H), 8.10 (s, 1 H), 7.69 (m, 1 H), 7.65 (s, 1 H), 7.46 (m, 1 H), 4.58 (s, 2 H), 3.42 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 137.4, 133.0, 132.6, 132.2, 132.0, 127.1, 127.0, 125.0, 122.3, 121.9, 74.4, 58.4. HRMS: m/z [M]+ calcd. for C12H10OBr2: 327.9098; found: 327.9108.2-(Methoxymethyl)-1,4-dimethylnaphthalene (6i; Table 3, entry 4): Yield: 41.7 mg (79%); beige solid; mp 39–42 °C; Rf = 0.54 (EtOAc–hexanes, 1:9). IR (KBr): 3070 (w), 2974 (m), 2923 (s), 2815 (m), 1716 (w), 1602 (w), 1512 (w), 1447 (m), 1389 (m), 1192 (m), 1104 (s), 1077 (m), 754 (s) cm–1. 1H NMR (600 MHz, CDCl3): δ = 8.11 (m, 1 H), 8.00 (m, 1 H), 7.52 (m, 2 H), 7.32 (s, 1 H), 4.64 (s, 2 H), 3.44 (s, 3 H), 2.67 (s, 3 H), 2.65 (s, 3 H). 13C NMR (125 MHz, CDCl3): δ = 133.0, 132.4, 132.3, 131.9, 130.6, 127.9, 125.4, 125.2, 124.6, 124.5, 73.3, 58.1, 19.3, 13.9. HRMS: m/z [M]+ calcd for C14H16O: 200.1201; found: 200.1207. 3-(Methoxymethyl)-1-methylnaphthalene (6j; Table 3, entry 5): Yield: 30.7 mg (73%); yellow oil; Rf = 0.32 (EtOAc–hexanes, 1:9). IR (neat): 3052 (w), 2980 (m), 2924 (s), 2918 (m), 1604 (m), 1509 (m), 1450 (m), 1193 (m), 1132 (m), 1100 (s), 910 (s), 868 (s), 734 (s) cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.98 (d, J = 7.8 Hz, 1 H), 7.83 (d, J = 7.2 Hz, 1 H), 7.64 (s, 1 H), 7.53–7.46 (m, 2 H), 7.31 (s, 1 H), 4.58 (s, 2 H), 3.42 (s, 3 H), 2.69 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 135.3, 134.7, 133.5, 132.2, 128.5, 126.4, 125.8, 125.7, 125.0, 124.0, 74.9, 58.2, 19.4. HRMS: m/z [M]+ calcd for C13H14O: 186.1045; found 186.1041.