Functionalized 1-alkoxy-1,3-dienes: Their preparation and applications in synthetic organic

The reaction of various alpha,beta-unsaturated acetals with two equivalents of the Schlosser reagent LIC-KOR [equimolar mixture of BuLi (LIC), and tBuOK (KOR)] gives 1-metalated (1E)-1-alkoxy-1,3-dienes. These products can be transformed into trienic derivatives that are apt to participate in intramolecular Diels-Alder (IMDA) cycloaddition reactions, and can also be transformed into bifunctional (gamma-halo-alpha-carbonyl) reagents. Moreover, the metalated dienes can be readily functionalized with suitable electrophiles to afford products that have been found to be useful reagents for the Stille and Suzuki cross-coupling reactions or arylated according to the conditions of the Heck process. Other significant syntheses of dienic and polyenic structures are reported along with some of their applications in organic synthesis.