Beatriz González Iglesias

The suzuki reaction in stereocontrolled polyene synthesis: Retinol (vitamin A), its 9- and/or 13-demethyl analogs, and related 9-demethyl-dihydroretinoids

Abstract A new synthesis of retinol (vitamin A) and 9- and/or 13-demethylretinols, with essentially complete control of regio- and stereochemistry, is described which is based on the thallium-accelerated, palladium-catalyzed cross-coupling reactions of (E)-1-alkenylboronic acids and (E)-1-alkenyl iodides (Suzuki reaction). The procedure has also been extended to the stereocontrolled synthesis of a series of 9-demethyl-dihydroretinoids of potential biological interest.

Stereospecific synthesis of 9-demethylretinoids via palladium-catalyzed vinylboronic acid-vinyl iodide cross coupling

A stereospecific synthesis of 9-demethylretinoids with either trans or 11-cis geometries, based on the thallium-accelerated palladium-catalyzed cross-coupling reactions of an (E)-1-alkenylboronic acid and (E) or (Z)-alkenyl iodides, is described. 9-Demethylretinoids with either trans or 11-cis geometries are stereospecifically prepared by the thallium-accelerated palladium-catalyzed cross coupling reactions of vinylboronic acid 10 and either (E)- or (Z)-vinyl iodides.

Synthesis and reactivity of new strained cyclic allene and alkyne precursors

The synthesis of ortho-(trimethylsilyl)vinyl triflates is described. Fluoride-induced decomposition of these triflates leads to the generation of strained cycloallenes and cycloalkynes under mild reaction conditions. The generation rate of these highly reactive intermediates can be modulated by modifying the solubility of the fluoride source. The slow generation of cyclic allenes and alkynes is a prerequisite for their use in homogeneous catalysis.