The diastereoselective cyclization of 2a to 5a, which was employed in our novel synthesis of dl-griseofulvin (7a), was studied in detail. It was found that the use of the metallic bases resulted in excellent diastereoselectively, whereas organic bases are ineffective for diastereoselective cyclization. Consequently, diastereoselective cyclization of 2 to 5 was proposed to proceed through the intramolecular Michael reaction under chelation control.
- chelation control
- diastereoselective Michael reaction
- reaction mechanism
ASJC Scopus subject areas
- Drug Discovery