Asymmetric Baylis-Hillman reactions of novel bornyl acrylate esters

Synthetic Communications

Volumn 29, Issue 12, 1999, Pages 2137-2146

  Evans, Melanie D ^a   Kaye, Perry T ^a  

^a RHODES UNIVERSITY   (South Africa)

Author keywords

[No Author keywords available]

Indexed keywords

ACRYLIC ACID DERIVATIVE; ESTER DERIVATIVE;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; CONFORMATION; CONFORMATIONAL TRANSITION; HYDROLYSIS; MOLECULAR MODEL; REACTION ANALYSIS; STEREOCHEMISTRY; STEREOISOMERISM; STEREOSPECIFICITY;

EID: 0032929967     PISSN: 00397911     EISSN: None     Source Type: Journal    
DOI: 10.1080/00397919908086209     Document Type: Article

References (19)

1. Baylis A.B. and Hillman, M.E.D., German Patent, 1972, 2155113, Chem. Abstr., 1972, 77, 33174.
2. Basavaiah, D., Rao, P.D. and Hyma, R.S., Tetrahedron, 1996, 52, 8001.
3. Drewes, S.E. and Roos, G.H.P., Tetrahedron, 1988, 44, 4653.
4. Basavaiah, D., Gowriswari, V.V.L., Sarma, P.K.S. and Dharma Rao, P., Tetrahedron Lett., 1990, 31, 1621.
5. Manickum, T. and Roos, G.H.P., Synth Commun., 1991, 21, 2269 ; Jensen, K.N. and Roos, G.H.P., S. Afr. J. Chem., 1992, 45, 112.
6. Manickum, T. and Roos, G.H.P., Synth Commun., 1991, 21, 2269 ; Jensen, K.N. and Roos, G.H.P., S. Afr. J. Chem., 1992, 45, 112.
7. Tohru Oishi, Hiroki Oguri and Masahiro Hirama, Tetrahedron : Asymmetry, 1995, 6, 1241.
8. Kündig, E.P., Long He Xu, Romanens, P. and Bernardinelli, G., Tetrahedron Lett., 1993, 34, 7049.
9. Basavaiah, D. and Dharma Rao, P., Synth. Commun., 1994, 24, 917.
10. See Kaye, P.T. and Robinson, R.S., S. Afr. J. Chem., 1998, 51, 47 and references cited therein.
11. See Kaye, P.T. and Ravindran, S.S., S. Afr. J. Chem., 1995, 48, 64 and references cited therein.
12. Evans, M.D., PhD thesis, Rhodes Univertsity, 1997.
13. Banks, A.R., Fibiger, R.F. and Jones, T., J. Org. Chem., 1977, 42, 3965.
14. The HCl generated in the reaction acting as acid catalyst.
15. The assumption being that the endo-face is more accessible to attack by the nucleophilic hydroxyl moiety than the exo-face.
16. 3-Quinuclidinol is known to enhance the reaction rate, presumably by hydrogen-bonding stabilisation of the intermediate zwitterion; see Ameer, F., Drewes, S.E., Freese, S. and Kaye, P.T., Synth. Commun., 1988, 18, 495.
17. The "exo-endo" designations are used to differentiate the two possible configurations at the pseudo-asymmetric centre (C-3) of the bornyl system (as in the esters 3 and 4).
18. 13C NMR chemical shifts of the Baylis-Hillman products were found to be concentration dependent, presumably reflecting intermolecular hydrogen bonding effects.
19. The two chemical shift values quoted in this format, here and below, refer to corresponding signals for the diastereomeric products, the combinations being necessarily tentative in some cases.