Synthesis of conjugated γ- and δ-lactones from aldehydes and ketones via a vinylation(allylation)-ring closing metathesis-oxidation sequence

Tetrahedron

Volumn 59, Issue 23, 2003, Pages 4085-4101

  Marco, J Alberto ^a   Carda, Miguel ^b   Rodríguez, Santiago ^b   Castillo, Encarnación ^b,c   Kneeteman, María N ^b,d  

^a UNIVERSITY OF VALENCIA   (Spain)

^b UNIVERSITAT JAUME I   (Spain)

^c UNIVERSIDAD CEU CARDENAL HERRERA   (Spain)

^d UNIVERSIDAD NACIONAL DEL LITORAL   (Argentina)

Author keywords

Allylic oxidation; Conjugated and lactones; Ring closing metathesis

Indexed keywords

DELTA LACTONE; ETHER DERIVATIVE; FURAN DERIVATIVE; GAMMA LACTONE DERIVATIVE; LACTONE DERIVATIVE; METHANOL DERIVATIVE; PYRAN DERIVATIVE; UNCLASSIFIED DRUG;

ALLYLATION; ARTICLE; CHEMICAL BOND; OXIDATION; PRIORITY JOURNAL; RING CLOSING METATHESIS; SUBSTITUTION REACTION; SYNTHESIS;

EID: 0038293051     PISSN: 00404020     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4020(03)00584-2     Document Type: Article

References (83)

1. Marco J.A., Carda M., González F., Rodríguez S., Castillo E., Murga J. J. Org. Chem. 63:1998;698-707.
2. We have recently published total syntheses of these three lactones: (a) Carda M., Rodríguez S., Segovia B., Marco J.A. J. Org. Chem. 67:2002;6560-6563 (b) Carda M., Rodríguez S., Castillo E., Bellido A., Díaz-Oltra S., Marco J.A. Tetrahedron. 59:2003;857-864. For further contributions of our group on the same field, see: (c) Carda M., González F., Castillo E., Rodríguez S., Marco J.A. Eur. J. Org. Chem. 2002;2649-2655 (d) Murga J., Falomir E., García-Fortanet J., Carda M., Marco J.A. Org. Lett. 2002;3447-3449 (e) Falomir E., Murga M., Carda M., Marco J.A. Tetrahedron Lett. 44:2003;539-541.
3. We have recently published total syntheses of these three lactones: (a) Carda M., Rodríguez S., Segovia B., Marco J.A. J. Org. Chem. 67:2002;6560-6563 (b) Carda M., Rodríguez S., Castillo E., Bellido A., Díaz-Oltra S., Marco J.A. Tetrahedron. 59:2003;857-864. For further contributions of our group on the same field, see: (c) Carda M., González F., Castillo E., Rodríguez S., Marco J.A. Eur. J. Org. Chem. 2002;2649-2655 (d) Murga J., Falomir E., García-Fortanet J., Carda M., Marco J.A. Org. Lett. 2002;3447-3449 (e) Falomir E., Murga M., Carda M., Marco J.A. Tetrahedron Lett. 44:2003;539-541.
4. We have recently published total syntheses of these three lactones: (a) Carda M., Rodríguez S., Segovia B., Marco J.A. J. Org. Chem. 67:2002;6560-6563 (b) Carda M., Rodríguez S., Castillo E., Bellido A., Díaz-Oltra S., Marco J.A. Tetrahedron. 59:2003;857-864. For further contributions of our group on the same field, see: (c) Carda M., González F., Castillo E., Rodríguez S., Marco J.A. Eur. J. Org. Chem. 2002;2649-2655 (d) Murga J., Falomir E., García-Fortanet J., Carda M., Marco J.A. Org. Lett. 2002;3447-3449 (e) Falomir E., Murga M., Carda M., Marco J.A. Tetrahedron Lett. 44:2003;539-541.
5. We have recently published total syntheses of these three lactones: (a) Carda M., Rodríguez S., Segovia B., Marco J.A. J. Org. Chem. 67:2002;6560-6563 (b) Carda M., Rodríguez S., Castillo E., Bellido A., Díaz-Oltra S., Marco J.A. Tetrahedron. 59:2003;857-864. For further contributions of our group on the same field, see: (c) Carda M., González F., Castillo E., Rodríguez S., Marco J.A. Eur. J. Org. Chem. 2002;2649-2655 (d) Murga J., Falomir E., García-Fortanet J., Carda M., Marco J.A. Org. Lett. 2002;3447-3449 (e) Falomir E., Murga M., Carda M., Marco J.A. Tetrahedron Lett. 44:2003;539-541.
6. We have recently published total syntheses of these three lactones: (a) Carda M., Rodríguez S., Segovia B., Marco J.A. J. Org. Chem. 67:2002;6560-6563 (b) Carda M., Rodríguez S., Castillo E., Bellido A., Díaz-Oltra S., Marco J.A. Tetrahedron. 59:2003;857-864. For further contributions of our group on the same field, see: (c) Carda M., González F., Castillo E., Rodríguez S., Marco J.A. Eur. J. Org. Chem. 2002;2649-2655 (d) Murga J., Falomir E., García-Fortanet J., Carda M., Marco J.A. Org. Lett. 2002;3447-3449 (e) Falomir E., Murga M., Carda M., Marco J.A. Tetrahedron Lett. 44:2003;539-541.
7. For reviews on olefin metathesis, see: (a) Armstrong S.K. J. Chem. Soc. Perkin Trans. 1. 1998;371-388 (b) Schrock R.R. Tetrahedron. 55:1999;8141-8153 (c) Fürstner A. Angew. Chem. Int. Ed. 39:2000;3012-3043 (d) Trnka T., Grubbs R.H. Acc. Chem. Res. 34:2001;18-29.
8. For reviews on olefin metathesis, see: (a) Armstrong S.K. J. Chem. Soc. Perkin Trans. 1. 1998;371-388 (b) Schrock R.R. Tetrahedron. 55:1999;8141-8153 (c) Fürstner A. Angew. Chem. Int. Ed. 39:2000;3012-3043 (d) Trnka T., Grubbs R.H. Acc. Chem. Res. 34:2001;18-29.
9. For reviews on olefin metathesis, see: (a) Armstrong S.K. J. Chem. Soc. Perkin Trans. 1. 1998;371-388 (b) Schrock R.R. Tetrahedron. 55:1999;8141-8153 (c) Fürstner A. Angew. Chem. Int. Ed. 39:2000;3012-3043 (d) Trnka T., Grubbs R.H. Acc. Chem. Res. 34:2001;18-29.
10. For reviews on olefin metathesis, see: (a) Armstrong S.K. J. Chem. Soc. Perkin Trans. 1. 1998;371-388 (b) Schrock R.R. Tetrahedron. 55:1999;8141-8153 (c) Fürstner A. Angew. Chem. Int. Ed. 39:2000;3012-3043 (d) Trnka T., Grubbs R.H. Acc. Chem. Res. 34:2001;18-29.
11. A preliminary report of the work described here has previously appeared: (a) Carda M., Castillo E., Rodríguez S., Uriel S., Marco J.A. Synlett. 1999;1639-1641 (b) All results reported here are part of the PhD Thesis of E. C., University of Castellón, Spain, 2000.
12. A preliminary report of the work described here has previously appeared: (a) Carda M., Castillo E., Rodríguez S., Uriel S., Marco J.A. Synlett. 1999;1639-1641 (b) All results reported here are part of the PhD Thesis of E. C., University of Castellón, Spain, 2000.
13. This strategy has also proven useful for the synthesis of conjugated δ-lactams: Rodríguez S., Castillo E., Carda M., Marco J.A. Tetrahedron. 58:2002;1185-1192.
14. For synthon nomenclature, see: Seebach D. Angew. Chem. Int. Ed. 18:1979;239-258.
15. For some representative examples, see: (a) Ghosh A.K., Cappiello J., Shin D. Tetrahedron Lett. 39:1998;4651-4654 (b) Bassindale M.J., Hamley P., Leitner A., Harrity J.P.A. Tetrahedron Lett. 40:1999;3247-3250 (c) Ramachandran P.V., Reddy M.V.R., Brown H.C. Tetrahedron Lett. 41:2000;583-586 (d) Nakashima K., Imoto M., Miki T., Miyake T., Fujisaki N., Fukunaga S., Mizutani R., Sono M., Tori M. Heterocycles. 56:2002;85-89.
16. For some representative examples, see: (a) Ghosh A.K., Cappiello J., Shin D. Tetrahedron Lett. 39:1998;4651-4654 (b) Bassindale M.J., Hamley P., Leitner A., Harrity J.P.A. Tetrahedron Lett. 40:1999;3247-3250 (c) Ramachandran P.V., Reddy M.V.R., Brown H.C. Tetrahedron Lett. 41:2000;583-586 (d) Nakashima K., Imoto M., Miki T., Miyake T., Fujisaki N., Fukunaga S., Mizutani R., Sono M., Tori M. Heterocycles. 56:2002;85-89.
17. For some representative examples, see: (a) Ghosh A.K., Cappiello J., Shin D. Tetrahedron Lett. 39:1998;4651-4654 (b) Bassindale M.J., Hamley P., Leitner A., Harrity J.P.A. Tetrahedron Lett. 40:1999;3247-3250 (c) Ramachandran P.V., Reddy M.V.R., Brown H.C. Tetrahedron Lett. 41:2000;583-586 (d) Nakashima K., Imoto M., Miki T., Miyake T., Fujisaki N., Fukunaga S., Mizutani R., Sono M., Tori M. Heterocycles. 56:2002;85-89.
18. For some representative examples, see: (a) Ghosh A.K., Cappiello J., Shin D. Tetrahedron Lett. 39:1998;4651-4654 (b) Bassindale M.J., Hamley P., Leitner A., Harrity J.P.A. Tetrahedron Lett. 40:1999;3247-3250 (c) Ramachandran P.V., Reddy M.V.R., Brown H.C. Tetrahedron Lett. 41:2000;583-586 (d) Nakashima K., Imoto M., Miki T., Miyake T., Fujisaki N., Fukunaga S., Mizutani R., Sono M., Tori M. Heterocycles. 56:2002;85-89.
19. 9b (allylmagnesium bromide or methallylmagnesium chloride in THF) were used for this purpose (see Section 3).
20. (a) Li C.-J., Chan T.H. Organic Reactions in Aqueous Media. 1997;Wiley, New York. Chapter 4.
21. (b) Miyaura N. Komiya S. Synthesis of Organometallic Compounds. 1998;Wiley, New York. Chapter 15.
22. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract precented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
23. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
24. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
25. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
26. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
27. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
28. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
29. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
30. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
31. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
32. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
33. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
34. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
35. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
36. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
37. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
38. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
39. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
40. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
41. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
42. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
43. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
44. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
45. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
46. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
47. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
48. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
49. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
50. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
51. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
52. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
53. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
54. Among the compounds cited in this paper, the following ones have previously been synthesized by means of various procedures (for each compound, the citation containing the most accurate NMR data is given): Abstract presented: Meyers A.I., Spohn R.F. J. Org. Chem. 50:1985;4872-4877.
55. Fürstner A., Langemann K. J. Am. Chem. Soc. 119:1997;9130-9136.
56. For examples of synthesis of tetrasubstituted olefins using B or similar catalysts bearing carbene ligands, see: (a) Scholl M., Trnka T.M., Morgan J.P., Grubbs R.H. Tetrahedron Lett. 40:1999;2247-2250 (b) Briot A., Bujard M., Gouverneur V., Nolan S.P., Mioskowski C. Org. Lett. 2:2000;1517-1519 (c) Yao Q. Org. Lett. 4:2002;427-430.
57. For examples of synthesis of tetrasubstituted olefins using B or similar catalysts bearing carbene ligands, see: (a) Scholl M., Trnka T.M., Morgan J.P., Grubbs R.H. Tetrahedron Lett. 40:1999;2247-2250 (b) Briot A., Bujard M., Gouverneur V., Nolan S.P., Mioskowski C. Org. Lett. 2:2000;1517-1519 (c) Yao Q. Org. Lett. 4:2002;427-430.
58. For examples of synthesis of tetrasubstituted olefins using B or similar catalysts bearing carbene ligands, see: (a) Scholl M., Trnka T.M., Morgan J.P., Grubbs R.H. Tetrahedron Lett. 40:1999;2247-2250 (b) Briot A., Bujard M., Gouverneur V., Nolan S.P., Mioskowski C. Org. Lett. 2:2000;1517-1519 (c) Yao Q. Org. Lett. 4:2002;427-430.
59. 4=H, n=1) could not be obtained through RCM of acrylate 6e neither with catalyst A nor with the second-generation ruthenium catalyst B. However, it was easily prepared from tertiary carbinol 5e via the allylation/RCM/oxidation sequence (Table 1).
60. 4=H, n=1) could not be obtained through RCM of acrylate 6e neither with catalyst A nor with the second-generation ruthenium catalyst B. However, it was easily prepared from tertiary carbinol 5e via the allylation/RCM/oxidation sequence (Table 1).
61. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
62. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
63. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
64. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
65. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
66. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
67. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
68. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
69. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
70. For examples of preparation of unsaturated oxygen heterocycles via RCM, see: (a) Delgado M., Martín J.D. Tetrahedron Lett. 38:1997;6299-6300 (b) Maier M.E., Bugl M. Synlett. 1998;1390-1392 (c) Sturino C.F., Wong J.C.Y. Tetrahedron Lett. 39:1998;9623-9626 (d) Schmidt B., Wildemann H. Synlett. 1999;1591-1593 (e) Edwards S.D., Lewis T., Taylor R.J.K. Tetrahedron Lett. 40:1999;4267-4270 (f) Oguri H., Sasaki S., Oishi T., Hirama M. Tetrahedron Lett. 40:1999;5405-5408 (g) Clark J.S., Kettle J.G. Tetrahedron. 55:1999;8231-8248 (h) Leeuwenburgh M.A., Kulker C., Duynstee H.I., Overkleeft H.S., van der Marel G.A., van Boom J.H. Tetrahedron. 55:1999;8253-8262 (i) Ahmed A., Öhler E., Mulzer J. Synthesis. 2001;2007-2010 (j) Rainier J.D., Cox J.M., Allwein S.P. Tetrahedron Lett. 42:2001;179-181.
71. (a) Kirkland T.A., Grubbs R.H. J. Org. Chem. 62:1997;7310-7318
72. (b) Chang S., Grubbs R.H. J. Org. Chem. 63:1998;864-866. It is worth mentioning here that we have had good results working at substrate concentrations of up to 0.1 M in some cases.
73. 3.
74. 4b which only gave dimerization products in the presence of A.
75. Dauben W.G., Lorber M., Fullerton D.S. J. Org. Chem. 34:1969;3587-3592.
76. Salmond W.G., Barta M.A., Havens J.L. J. Org. Chem. 43:1978;2057-2059.
77. 4=Me, n=0) gave compound ii, which has additionally incorporated a 3,5-dimethylpyrazole moiety from the oxidation reagent. This contrasts with the behaviour of the corresponding dihydrofurans without the ring methyl group, which gave the expected oxidation products (Table 2). Most likely, the additional methyl group sterically retards the oxidation of the methylene carbon to such an extent that attack at the methine carbon becomes competitive.
78. Wu Z., Nguyen S.T., Grubbs R.H., Ziller J.W. J. Am. Chem. Soc. 117:1995;5503-5511.
79. Allylic substitution has been shown to decrease the rate of RCM processes: Ulman M., Grubbs R.H. Organometallics. 17:1998;2484-2489. It has been reported, however, that allylic hydroxyl groups have an accelerating effect: Hoye T.R., Zhao H. Org. Lett. 1:1999;1123-1125.
80. Allylic substitution has been shown to decrease the rate of RCM processes: Ulman M., Grubbs R.H. Organometallics. 17:1998;2484-2489. It has been reported, however, that allylic hydroxyl groups have an accelerating effect: Hoye T.R., Zhao H. Org. Lett. 1:1999;1123-1125.
81. Hérisson J.-L., Chauvin Y. Makromol. Chem. 141:1971;161-176.
82. Eliel E.L., Wilen S.H. Stereochemistry of Carbon Compounds. 1994;Wiley, New York. pp 682-684.
83. 4=H, n=1) has been secured with the aid of an X-ray diffaction analysis. Crystallographic data (excluding structure factors) have been deposited at the Cambridge Crystallographic Data Center as supplementary material with reference CCDC-199804. Copies of the data can be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK [fax: +44(0)-1223-336033 or e-mail: deposit@ccdc.cam.ac.uk].