La presence d'un groupe acetoxy ou tetrahydropyrannyloxy en position β du groupe benzenesulfonyl conduit a la formation d'une liaison unique acetylenique ou polyenique donnant lieu a la formation de toute une variete de composes enyniques diyniques et polyeniques
La Presence d'un groupe acetoxy ou tetrahydropyrannyloxy en position β du groupe bensulfonyl pipe a laformation d'une liaison unique 炔
BAKER’S YEAST HYDROGENATION OF CARBONYL ACTIVATED DOUBLE BONDS. ENANTIOSELECTIVE SYNTHESIS OF THE (<i>S</i>)-FORM OF THE DIHYDROTERPENEDIOL SECRETED BY<i>DANAUS CHRYSIPPUS</i>AND OF A PHEROMONE OF<i>CALLOSOBRUCHUS CHINENSIS</i>L.
The (S)-forms of (E)-3,7-dimethyl-2-octene-1,8-diol (secreted by male danaid butterflies) and of (E)-3,7-dimethyl-2-octene-1,8-dioic acid (a pheromone of the azuki bean weevil) were synthesized via stereoselective hydrogenation by baker’s yeast of the carbonyl activated double bond of achiral precursors.
Natural (E)-(7R, 11R)-Phytol (1), a component of the chlorophyll molecule, vitamin K1 (2) and other natural compounds, was synthesized in enantiomerically and diastereomerically pure form by Li2CuCl4-induced coupling of two C10-units (8, 12). Both these units were prepared from geraniol (3) via enzymatic enantioselective hydrogenation of activated double bonds.