CHEMISTRY OF CARBANIONS .34. ALKYLATION OF A 1-DECALONE ENOLATE WITH ABNORMAL GEOMETRY

Solutions of the lithium enolate 10 have been prepared by appropriate transformations of the ketones 8 and 9. Both an X-ray structure determination of the derived enol ester 26 and conformational calculations on the related olefin 27 suggest that the favored conformations of the enolate 10 are the twist-boat conformers 28a and 28b. Reaction of this enolate 10 with methyl iodide formed predominantly the cis-fused decalone 17. This result is in better agreement with an early, reactant-like transition state for the alkylation reaction rather than a late, product-like transition state that resembles the geometry of the products in their initially formed conformations. © 1979, American Chemical Society. All rights reserved.