The sesquiterpene (+)-gossonorol is prepared in only three synthetic steps in 60% overall yield and 82% ee from commercially available reagents. The key asymmetric step is the catalytic enantioselective addition of dimethylzinc to 5-methyl-1-(2-methylphenyl) hex-4-en-1- one catalyzed by chiral isoborneolsulfonamide ligands in the presence of titanium tetraisopropoxide. The modular approach allows the synthesis not only of the ...