Lewis-acid promoted addition of 2-trimethylsilyloxyfuran to nitrones: Synthesis and absolute configuration of tetrahydro-2-benzyl-3-(1-benzyloxyethyl)-furo[2,3-d]isoxazol-5(2H)ones

Tetrahedron Asymmetry

Volumn 7, Issue 4, 1996, Pages 1059-1068

  Castellari, Carlo ^a   Lombardo, Marco ^a   Pietropaolo, Graziano ^a   Trombini, Claudio ^a  

^a UNIVERSITY OF BOLOGNA   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

FURO[2,3 D]ISOXAZOLE DERIVATIVE; ISOXAZOLE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; DRUG SYNTHESIS; PRIORITY JOURNAL; REACTION ANALYSIS; STEREOCHEMISTRY; X RAY ANALYSIS;

EID: 0029994555     PISSN: 09574166     EISSN: None     Source Type: Journal    
DOI: 10.1016/0957-4166(96)00110-3     Document Type: Article

References (22)

1. Dhavale, D.D.; Trombini, C. Heterocycles, 1992, 34, 2253.
2. (a) Dhavale, D.D.; Trombini, C. J. Chem. Soc. Chem. Commun. 1992, 1268;
3. (b) Camiletti, C.; Dhavale, D.D.; Gentilucci, L.; Trombini, C. J. Chem. Soc. Perkin Trans. 1, 1993, 3157.
4. (a) Kita, Y.; Ithoc, F.; Tamura, O.; Ke, Y.Y.; Tamura, Y. Tetrahedron Lett. 1987, 28, 1431;
5. (b) Kita, Y.;, Tamura, O.; Ithoc, F.; Kishino, H.; Miki, T.; Kohno, M.; Tamura, Y. J. Chem. Soc. Chem. Comm. 1988, 761.
6. Camiletti, C.; Dhavale, D.D.; Donati, F.; Trombini, C. Tetrahedron Lett, 1995, 36, 7293.
7. For an excellent review on the use of 2-trimethylsilyloxyfuran in the synthesis of homochiral compounds see: Casiraghi, G.; Rassu, G. Synthesis, 1995, 607.
8. Camiletti, C.; Poletti, L.; Trombini, C. J. Org. Chem., 1994, 59, 6843.
9. 3CHOBn, 6), 236 (2), 195 (2), 91 (100).
10. Upon irradiation at H3a isomers 10a and 10c only showed a 10-15% enhancement of H6a, while isomers 10b and 10d, besides to H6a showed a 4-7% NOE effect at H3, thus confirming the C3a-C3 syn stereorelationship.
11. Bond distances of the bicyclic system are in accord with the interatomic distances found in the structure of (3R,6R,7R,11S)-7-acetoxymethyl-5,8,10-trioxa-1-azatricyclo[4.3.2.0]undecan-4- one: see Suwiniska, K.; Panfil, I.; Belzecki, C.; Chimilewski, M. Acta Crystallogr., Sect. C, 1989, C45, 1836.
12. Among weak directional interactions, intermolecular CH···O hydrogen bonds are considered important factors in determining crystal packing: see Desiraju, G.R. Angew. Chem. Int. Ed. Engl., 1995, 34, 2311.
13. The inspection of molecular model of C shows that a possible C3aH3a···O2 H-bond should be destabilized by an eclipsed interaction between C1-C7 and C3-N2 bonds.
14. Carreira, E.M.; Singer, R.A. Tetrahedron Lett., 1994, 35, 4323.
15. Denmark, S.E.; Chen, C.-T. Tetrahedron Lett., 1994, 55, 4327.
16. Hollis, T.K.; Bosnich, B. J. Am. Chem. Soc., 1995, 117, 4570.
17. On the basis of 1,3-allylic strain the conformation presenting the C-H bond almost coplanar to the C=NOMLn framework should be the stablest arrangement ; see Hoffmann, R.W. Chem. Rev., 1989, 89, 1841.
18. Jones, G.B.; Chapman, B.J. Synthesis, 1995, 475.
19. Paterson, I.; Goodman, J.M.; Lister, M.A.; Schumann, R.C.; McClure, C.K.; Norcross, R.D. Tetrahedron, 1990, 46, 4663.
20. (a) Sheldrick, G.M. Acta Crystallogr. Sect. A, 1990, 46, 467;
21. (b) Sheldrick, G.M. J. Appl. Cryst. in the press.
22. Atomic coordinates, bond lenghts and angles, and thermal parameters have been deposited at the Cambridge Data Center.