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

Andrew Tigchelaar; Jamie Haner; Emily Carlson; William Tam

doi:10.1055/s-0034-1378581

Synlett, Inhaltsverzeichnis

Synlett 2014; 25(16): 2355-2359
DOI: 10.1055/s-0034-1378581

letter

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

Authors

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

Abstract

Alle Artikel dieser Rubrik

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

Volltext

Referenzen

References and Notes
1 Bournaud C, Chung F, Luna AP, Pasco M, Errasti G, Lecourt T, Micouin L. Synthesis 2009; 869
2 Tam W, Cockburn N. Synlett 2010; 1170
3 Rayabarapu DK, Cheng C.-H. Acc. Chem. Res. 2007; 40: 971
4 Lautens M, Fagnou K, Heibert S. Acc. Chem. Res. 2003; 36: 48
5 Woo S, Keay BA. Synthesis 1996; 669
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
8 Lautens M, Dockendorff C. Org. Lett. 2003; 5: 3695
9 Duan J, Cheng C.-H. Tetrahedron Lett. 1993; 34: 4019
10 Feng C, Nandi TS, Cheng C.-H. J. Org. Chem. 1999; 64: 3538
11 Lautens M, Hiebert S. J. Am. Chem. Soc. 2004; 126: 1437
12 Wu MS, Jeganmohan M, Cheng C.-H. J. Org. Chem. 2005; 70: 9545
13 Leong P, Lautens M. J. Org. Chem. 2004; 69: 2194
14 Bertozzi F, Pineschi M, Macchia F, Arnold LA, Minnaard AJ, Feringa BL. Org. Lett. 2002; 4: 2703
15 Fan E, Shi W, Lowary TL. J. Org. Chem. 2007; 72: 2917
16 Madan S, Cheng C.-H. J. Org. Chem. 2006; 71: 8312
17 Lautens M, Rovis T. Tetrahedron 1999; 55: 8967
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
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
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
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
25 Nakata D, Sakuma T, Kono K, Sato S, Tani S, Kunishima M. Chem. Pharm. Bull. 2001; 49: 97
26 Ahern C, Darcy R. Synth. Commun. 1998; 28: 971
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
29 Shibata T, Ueno Y, Kanda K. Synlett 2006; 411
30 Engler TA, Shechter H. J. Org. Chem. 1999; 64: 4247
31 Hughes TS, Carpenter BK. J. Chem. Soc., Perkin Trans. 2 1999; 2291
32 Myers AG. Tetrahedron Lett. 1987; 28: 4493
33 Álvarez-Bercedo P, Martin R. J. Am. Chem. Soc. 2010; 132: 17352
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; R_f = 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; R_f = 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; R_f = 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; R_f = 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; R_f = 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; R_f = 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; R_f = 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, Δδ_AB = 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; R_f = 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; R_f = 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; R_f = 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.

Zusatzmaterial

Supporting Information (PDF)