The Enantioselective Conversion of Three-Membered Ring Sulfoxides (Episulfoxides) into Alkenyl Sulfoxides using Chiral Lithium Amide Bases

Synlett

Volumn 1997, Issue 8, 1997, Pages 919-920

  Blake, Alexander J ^a   Westaway, Susan M ^a   Simpkins, Nigel S ^a  

^a UNIVERSITY OF NOTTINGHAM   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0002543147     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1997-948     Document Type: Article

References (18)

1. For a review, see Cox, P. J.; , Simpkins, N. S. Tetrahedron:Asymmetry 1991, 2, 1.
2. Armer, R.; Begley, M. J.; Cox, P. J.; Persad, A.; Simpkins, N.S. J. Chem. Soc., Perkin Trans. 1 1993, 3099.
3. Armer, R.; PhD Thesis, University of Nottingham, 1994.
4. (a) Bonini, B. F.; Maccagnani, G.; Mazzanti, G.; Piccinelli, P. Tetrahedron Lett. 1979, 3987.
5. (b) Bonini, B. F.; Maccagnani, G.; Mazzanti, G.; Zani, P. Gazz. Chim. Ital. 1990, 120, 115.
6. (c) Schwan, A. L.; Pippert, M. F.; Pham, H. H.; Roche, M. R. J. Chem. Soc., Chem. Commun. 1993, 1312.
7. (d) Refvik. M. D.; Froese, R. D. J.; Goddard, J. D.; Pham, H. H.; Pippert, M. F.; Schwan, A. L. J. Am. Chem. Soc. 1995, 117, 184.
8. Giblin, G. M. P.; Ramcharitar, S. H.; Simpkins, N. S. Tetrahedron Lett. 1988, 29, 4197.
9. Chan, T. H.; Finkenbine, J. R. J. Am. Chem. Soc. 1972, 94, 2880.
10. The exo-selective sulfoxidation of the ring-fused episulfides is to be expected, and was confirmed in the case of 7 by X-ray crystallography. At present the other examples are assumed to be analogous.
11. For the synthesis of the chiral diamine, see Bambridge, K.; Begley, M. J.; Simpkins, N. S. Tetrahedron Lett. 1994, 35, 3391.
12. 2 requires C, 52.0: H, 5.4; S, 21.3%.
13. iPrOH in hexane as eluant (UV detection at 254 nm).
14. The absolute configuration was established by the collection of low-temperature data, including Friedel equivalents, and by refinement of a Flack parameter (value 0.00(6)), see Flack, H. D. Acta Crystallogr., Sect. A 1983, 39, 876.
15. Estimation of the ee of 12 was not possible. The ee of the derived sulfone 13 was determined using the same conditions used for 8.
16. The diastereomeric episulfoxides were obtained via the corresponding epoxides, the relative configuration of which has been assigned, see Hodgson, D. M.; Witherington, J.; Moloney, B. A. J. Chem. Soc., Perkin Trans. 1 1994, 3373.
17. iPrOH in hexane as eluant. The two enantiomers were eluted with retention times of ra. 25 and 27 minutes, with the first eluted being the major component when starting with 19, and the second predominating in the case of 14.
18. The exo-episulfide corresponding to 20 was prepared as described previously, see Emsley, J.; Griffiths, D. W.; Jayne, G. J. J. J. Chem. Soc., Perkin Trans. 1 1979, 228.