Two-carbon homologation of aldehydes via silyl ketene acetals. 2. Study of the stereochemical control in the formation of (E)-alkenoic acids.
The condensation of C,O,O-tris(trimethylsilyl)ketene acetal 1 with aldehydes 2 in the presence of catalytic amounts of mercuric iodide at room temperature affords syn and anti beta-trimethylsiloxy alpha-trimethylsilyl alkanoic acid silyl esters 3 in good yields. These new compounds gave, under acidic or basic conditions, E and (or) Z enoic acids 4. The paths for the formation of these alkenoic acids are discussed.
Bellassoued
M
M
Laboratoire de Synthèse Organométallique associé au CNRS, Université de Cergy-Pontoise, Bâtiment des Sciences de la Matière, 5 Mail Gay Lussac, Neuville sur Oise, 95031 Cergy-Pontoise Cedex, France. moncef.bellasoued@chim.u-cergy.fr
Mouelhi
S
S
Lensen
N
N