Ynolates were found to react with alpha-alkoxy-, alpha-siloxy-, and alpha-aryloxyketones at room temperature to afford tetrasubstituted olefins with high Z selectivity. Since the geometrical selectivity was determined in the ring opening of the beta-lactone enolate intermediates, the torquoselectivity was controlled by the ethereal oxygen atoms. From experimental and theoretical studies, the high Z
Synthesis of Highly Substituted Furans by a Cascade of Formal <i>anti</i>-Carbopalladation/Hydroxylation and Elimination
作者:Theresa Schitter、Naveen J. Roy、Peter G. Jones、Daniel B. Werz
DOI:10.1021/acs.orglett.8b03732
日期:2019.2.1
substituted furans are generated by a cascade of formal anti-carbopalladation, attack of a nucleophilic hydroxy group, and aromatization by elimination of the emerging dihydrofuran derivative. Mono-, di-, and trisubstituted furans were obtained in good to excellent yields. When we attempted to access tetrasubstituted furan derivatives, an additional rearrangement was observed that resulted in the formation