Download PDF
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
› Author Affiliations
Further Information

Publication History

Received: 27 March 2014

Accepted after revision: 11 July 2014

Publication Date:
06 August 2014 (online)

    Permissions and Reprints All articles of this category


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.
  • Supporting Information
 

  • References and Notes

  • 1 Bournaud C, Chung F, Luna AP, Pasco M, Errasti G, Lecourt T, Micouin L. Synthesis 2009; 869
    Article in Thieme Connect
  • 2 Tam W, Cockburn N. Synlett 2010; 1170
    Article in Thieme Connect
  • 3 Rayabarapu DK, Cheng C.-H. Acc. Chem. Res. 2007; 40: 971
    CrossrefPubMed
  • 4 Lautens M, Fagnou K, Heibert S. Acc. Chem. Res. 2003; 36: 48
    CrossrefPubMed
  • 5 Woo S, Keay BA. Synthesis 1996; 669
    Article in Thieme Connect
  • 6 Chiu P, Lautens M. Top. Curr. Chem. 1997; 190: 1
  • 7 Lautens M, Dockendorff C, Fagnou K, Malicki A. Org. Lett. 2002; 4: 1311
    CrossrefPubMed
  • 8 Lautens M, Dockendorff C. Org. Lett. 2003; 5: 3695
    Crossref
  • 9 Duan J, Cheng C.-H. Tetrahedron Lett. 1993; 34: 4019
    Crossref
  • 10 Feng C, Nandi TS, Cheng C.-H. J. Org. Chem. 1999; 64: 3538
    CrossrefPubMed
  • 11 Lautens M, Hiebert S. J. Am. Chem. Soc. 2004; 126: 1437
    Crossref
  • 12 Wu MS, Jeganmohan M, Cheng C.-H. J. Org. Chem. 2005; 70: 9545
    CrossrefPubMed
  • 13 Leong P, Lautens M. J. Org. Chem. 2004; 69: 2194
    CrossrefPubMed
  • 14 Bertozzi F, Pineschi M, Macchia F, Arnold LA, Minnaard AJ, Feringa BL. Org. Lett. 2002; 4: 2703
    CrossrefPubMed
  • 15 Fan E, Shi W, Lowary TL. J. Org. Chem. 2007; 72: 2917
    Crossref
  • 16 Madan S, Cheng C.-H. J. Org. Chem. 2006; 71: 8312
    Crossref
  • 17 Lautens M, Rovis T. Tetrahedron 1999; 55: 8967
    Crossref
  • 18 de Meijere A. Angew. Chem. Int. Ed. Engl. 1979; 18: 809
  • 19 McKee M, Haner J, Carlson E, Tam W. Synthesis 2014; 46: 1518
    Article in Thieme Connect
  • 20 Frejaville C, Jullien R. Tetrahedron Lett. 1971; 23: 2039
  • 21 Bertz SH, Dabbagh G, Cook JM, Honkan V. J. Org. Chem. 1984; 49: 1739
    Crossref
  • 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
    Crossref
  • 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
    Crossref
  • 25 Nakata D, Sakuma T, Kono K, Sato S, Tani S, Kunishima M. Chem. Pharm. Bull. 2001; 49: 97
    Crossref
  • 26 Ahern C, Darcy R. Synth. Commun. 1998; 28: 971
    Crossref
  • 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
    Crossref
  • 29 Shibata T, Ueno Y, Kanda K. Synlett 2006; 411
  • 30 Engler TA, Shechter H. J. Org. Chem. 1999; 64: 4247
    Crossref
  • 31 Hughes TS, Carpenter BK. J. Chem. Soc., Perkin Trans. 2 1999; 2291
  • 32 Myers AG. Tetrahedron Lett. 1987; 28: 4493
    Crossref
  • 33 Álvarez-Bercedo P, Martin R. J. Am. Chem. Soc. 2010; 132: 17352
    Crossref
  • 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.