Synthesis of 2-substituted chromenes via ring-closing metathesis and stable 1-benzopyrylium ions

Tetrahedron Letters

Volumn 41, Issue 31, 2000, Pages 5979-5983

  Doodeman, Robin ^a   Rutjes, Floris P J T ^b   Hiemstra, Henk ^a  

^a Univ A   (Netherlands)

^b RADBOUD UNIVERSITY NIJMEGEN   (Netherlands)

Author keywords

1 benzopyrylium ions; Benzyloxy 1,2 propadiene; Chromenes; Ring closing metathesis

Indexed keywords

ACETAL; ALLYL COMPOUND; BENZOPYRAN DERIVATIVE; CHROMENE DERIVATIVE;

ALKYLATION; ARTICLE; CATALYST; COLUMN CHROMATOGRAPHY; PROTON NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS; SYNTHESIS;

EID: 0034729978     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(00)00955-2     Document Type: Article

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20. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
21. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
22. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
23. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
24. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
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26. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
27. For other recent examples of ether formation via RCM, see: (a) Crimmins, M. T.; Choy, A. L. J. Am. Chem. Soc. 1999, 121, 5653. (b) Delgado, M.; Martin, J. D. J. Org. Chem. 1999, 64, 4798. (c) Fürstner, A.; Muller, T. J. Am. Chem. Soc. 1999, 121, 7814. (d) Schmidt, B.; Wildemann, H. Synlett 1999, 10, 1591. (e) Carda, M.; Castillo, E.; Rodriguez, S.; Uriel, S.; Marco, J. A. Synlett 1999, 10, 1639. (f) Wong, J. C. Y.; Lacombe, P.; Sturino, C. F. Tetrahedron Lett. 1999, 40, 8751. (g) Bujard, M.; Briot, A.; Gouverneur, V.; Mioskowski, C. Tetrahedron Lett. 1999, 40, 8785. (h) Sturino, C. F.; Wong, J. C. Y. Tetrahedron Lett. 1998, 39, 9626. (h) Oishi, T.; Nagumo, Y.; Hirama, M. Synlett 1997, 980. (i) Leeuwenburgh, M. A.; Overkleeft, H. S.; van der Marel, G. A.; van Boom, J. H. Synlett 1997, 1263. (j) Clark, J. S.; Hamelin, O.; Hufton, R. Tetrahedron Lett. 1998, 39, 8321.
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44. 2): δ=9.87 (dd, J=1.8, 4.1 Hz, 1H, H2), 9.72 (dt, J=0.7, 8.3 Hz, 1H, H4), 8.44-8.51 (m, 2H), 8.39 (dd, J=4.1, 8.3 Hz, 1H, H3), 8.34 (dd, J=0.4, 8.8 Hz, 1H), 8.13 (dt, J=0.9, 7.2 1H).