0000000000628268
AUTHOR
Mercedes Torres
Efficient Addition of Acid Enediolates to Epoxides
We report new conditions to facilitate the addition of dianions of carboxylic acids to epoxides as an alternative method to the use of aluminum enolates. These conditions require the use of a sub-stoichiometric (10%) amount of amine for dianion generation and the previous activation of the epoxide with LiCl. Other Lewis acids have been shown to be less effective. Yields are good but only low diastereoselectivity is attained, which has not been controlled despite attempts at optimization. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Experimental and theoretical investigations for the tandem alkylation–isomerization reactions between unsaturated carboxylic acids and allyl halides
Abstract—Alkylation of dienediolates from unsaturated carboxylic acids with allylic halides when followed by solventless thermaltreatment at 150 to 2008C afford rearranged products on a trend highly dependent on the acarbon substitution. Thus, 2,2-bisallylated acidswith H atoms at C-2 lead to its 1,3-shift, whereas 2-methyl-2,2-bisallylated acids lead to the corresponding Cope rearrangement product. Inthe latter case, this tandem allylation-Cope reaction lead, in a highly regio and diastereoselective way, to products not accessible from directalkylation. B3LYP/6-31G p energies for the compounds involved at these isomerizations are in reasonable agreement with the experiments,allowing to exp…