Electrophilic carbocyclisations, including tandem processes, using novel cobaloxime π-Cation intermediates

Synlett

Volumn , Issue 7, 1998, Pages 783-785

  Kettschau, Georg ^a   Pattenden, Gerald ^a  

^a UNIVERSITY OF NOTTINGHAM   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001776990     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: None     Document Type: Article

References (13)

1. Kettschau, G; Pattenden, G.; Tetrahedron Lett. 1998, 39, 2027;
2. cf Gill, G.B.; Pattenden, G.; Roan, G.A. Tetrahedron Lett. 1996, 37, 9369.
3. Gage, J.L.; Branchaud, B.P. J. Org. Chem. 1996, 61, 831;
4. Gage, J.L.; Branchaud, B.P. Tetrahedron Lett. 1997, 38, 7007.
5. Becker, D.; Haddad, N. Tetrahedron 1993, 49, 947.
6. Julia, M.; Descoins, C.; Baillarge, M.; Jacquet, B.; Uguen, D.; Groeger, F.A. Tetrahedron 1975, 31, 1737.
7. Klunder, J.M.; Onami, T.; Sharpless, K.B. J. Org. Chem. 1989, 54, 1295.
8. Tamura, M.; Kochi, J. Synthesis 1971, 303.
9. 3): υ = 2927, 2854 (C-H), 1604, 1563 (C=C). Accurate MS (FAB): M - [Co]: required 202.1596, found 202.1376.
10. The cycloalkenylcobaloximes 12, 14 and 15 were produced as varying mixtures of double bond positional isomers, as indicated in the formulae.
11. cf Tanis, S.P.; Raggon, J. W. J. Org. Chem. 1987, 52, 819; and reference 2 above.
12. Hatakeyama, S.; Numata, H.; Osanai, K.; Takano, S. J. Chem. Soc., Chem. Comm. 1989, 1893.
13. 4) and evaporated. The residue was purified by column chromatography (12 g deactivated silica, gradient elution (EtOAc/petroleum ether (40-60°C) 3:2; EtOAc 100%, then EtOAc/EtOH 9:1) to give the tricycle 21 (5 mg, 30%) as an orange solid.