CsCO-Promoted reaction of tertiary bromopropargylic alcohols and phenols in DMF: a novel approach to α-phenoxyketones.

The reaction of bromopropargylic alcohols with phenols in the presence of CsCO/DMF affords α-phenoxy-α'-hydroxyketones (1:1 adducts) and α,α-diphenoxyketones (1:2 adducts) in up to 92% and 24% yields, respectively. Both products are formed via ring opening of the same intermediates, 1,3-dioxolan-2-ones, generated in situ from bromopropargylic alcohols and CsCO.

A domino reaction of alpha,beta-acetylenic gamma-hydroxy nitriles with arenecarboxylic acids: an unexpected facile shortcut to 4-cyano-3(2H)-furanones.

An unexpected facile domino reaction of alpha,beta-acetylenic gamma-hydroxy nitriles with arenecarboxylic acids (Et(3)N, MeCN, 20-25 degrees C, 48 h) affords 4-cyano-3(2H)-furanones in 67-86% yield. The reaction is triggered by the addition of an arenecarboxylic acid to a triple bond, followed by the domino reaction sequence: intramolecular transesterification-enol formation and Claisen condensation of the ketoacetonitrile tautomer with ester functional group.

Stereochemical study of iminodihydrofurans based on experimental measurements and SOPPA calculations of (13)C-(13)C spin-spin coupling constants.

Configurational assignment and conformational analysis of a series of iminodihydrofurans obtained from cyanoacetylenic alcohols were performed on the basis of experimental measurements and high-level ab initio calculations of their (13)C-(13)C spin-spin coupling constants. The title compounds were shown to form and exist in solution as the individual Z isomers, adopting the orthogonal orientation of the amino, alkylamino and dialkylamino groups and the s-trans orientation of the CONH(2) group at the C(4) position of the 2,5-dihydro-2-iminofuran moiety.