An Expedient Protocol for Cyclopentenone Annulation

Abstract

A convenient and general protocol for the cyclopentenone annulation process is described.

Key words

cyclopentenone annulation - Wittig olefination - Claisen rearrangement - Wacker oxidation - polyquinanes

References

• 1 Tsunoda T. Kodama M. Ito S. Tetrahedron Lett.  1983,  24:  83 
• 2 Pattenden G. Teague SJ. Tetrahedron Lett.  1982,  23:  5471 
• 3 Piers E. Karunaratne V. J. Chem. Soc., Chem. Commun.  1983,  935 
• 4 Curran DP. Chen M.-H. Tetrahedron Lett.  1985,  26:  4991 
• 5 Billington DC. Kerr WJ. Pauson PL. J. Organomet. Chem.  1987,  328:  223 
• 6 Sampath V. Lund EC. Knudsen MJ. Olmstead MM. Schore NE. J. Org. Chem.  1987,  52:  3595 
• 7 Ramaiah M. Synthesis  1984,  529 
• 8 Mehta G. Srikrishna A. Chem. Rev.  1997,  97:  671 
• 9 Paquette LA. Top. Curr. Chem.  1984,  119:  1 
• 10 Hudlicky T. Price JD. Chem. Rev.  1989,  89:  1467 
• 11 Curran DP. Synthesis  1988,  417 
• 12 Curran DP. Synthesis  1988,  489 
• 13 Schore NE. Chem. Rev.  1988,  88:  1081 
• 14 Trost BM. Angew. Chem., Int. Ed. Engl.  1986,  25:  1 ; Angew. Chem. 1986, 9, 1
• 15 Ellison RA. Synthesis  1973,  397 
• 16 Trost BM. Chem. Soc. Rev.  1982,  141 
• 17 Paquette LA. Aldrichimica Acta  1984,  17:  43 
• 18 Negeshi E. Coperet C. Ma S. Liou S.-Y. Liu F. Chem. Rev.  1996,  96:  365 
• 19 Mehta G. Karra SR. Tetrahedron Lett.  1991,  32:  3215 
• 20a Kulkarni MG. Pendharkar DS. Tetrahedron Lett.  1997,  53:  3167 
• 20b Kulkarni MG. Pendharkar DS. J. Chem. Soc., Perkin Trans. 1  1997,  3127 
• 21 Kulkarni MG. Pendharkar DS. Rasne RM. Tetrahedron Lett.  1997,  38:  1459 
• 22a Claisen L. Chem. Ber.  1912,  45:  3157 
• 22b Claisen L. Chem. Ber.  1936,  69:  77 
• 23 Rhoads SJ. Raulins NR. Org. React.  1975,  22:  1 
• 24 von Smidt J. Hafner W. Jira R. Sedlmeier J. Sieber R. Angew. Chem.  1959,  71:  176 
• 27 Atwater NW. J. Am. Chem. Soc.  1960,  82:  2847 
• 28 Conia JM. Sandre-LeCratz A. Tetrahedron Lett.  1962,  3:  505 
• 29 Newman MS. DeVries V. Darlak R. J. Org. Chem.  1966,  31:  2171 
• 30 Herrmann JL. Kieczykowski GR. Schlessinger RH. Tetrahedron Lett.  1973,  26:  2433 

25

However, in some cases [20] it was possible to separate and characterize the individual E and Z isomers.

26

Under aldol condensation conditions product 5h underwent isomerisation to compound 5j through a deconjugation process [27-30] via 5i (Scheme [1)] .

31

Calculated on the basis of recovered substrate.

32

All the new compounds gave satisfactory analytical and spectroscopic data (Table [2] ).