We have developed a programmable and diversity-oriented synthetic scheme for tetrasubstituted olefins through a site-selective and sequential assembly of pi-components onto a C=C core of vinyl 2-pyrimidyl sulfide. Noteworthy features are that (i) all components assembled stem from readily available organic halides or their Grignard reagents, (ii) the installation at the desired position can be achieved by the addition of the components in the appropriate order, and (iii) simple alteration of addition order in the sequence results in the production of all possible regio- and stereoisomers of multisubstituted olefins.

A rapid synthesis of CDP840 (a potential therapeutic agent for asthma), using 2-pyrimidyl vinyl sulfide as a platform, has been established. This method includes a stereoselective double Mizoroki-Heck-type arylation, a Liebeskind-Srogl-type cross-coupling reaction, and a Pd/C-catalyzed hydrogenation.

Keywords: Diastereoselectivity / Palladium / P ligands / Quaternary carbon center / Natural products Regio-and diastereoselective nucleophilic substitution of 2-methylacetoacetate with a chiral non-racemic π-allyl Pd complex creates consecutive chiral non-racemic quaternary and tertiary carbon centers. σ-Bond formation between the reface of the π-allyl Pd complex and the re-face of the enol

Diastereoselective syntheses Diastereoselective syntheses O 0031Construction of Consecutive Chiral Non-racemic Quaternary and Tertiary Carbon Centers: A Short Synthetic Route to (-)-Acetomycin. -A highly regioselective and diastereoselectiVe Pd-catalyzed allylic alkylation of optical active allyl acetate (II) is developed for asymmetric construction of quaternary carbon centers and applied to the shortest synthesis of acetomycin (IX) hitherto reported. -(UENISHI*, J.; KAWATSURA, M.; IKEDA, D.; MURAOKA, N.; Eur. J. Org. Chem. 2003, 20, 3909-3912; Kyoto Pharm. Univ., Misasagi, Yamashina, Kyoto 607, Japan; Eng.) -Nuesgen 07-035

Polyphenylalkene derivatives Q 0740Sequential Assembly Strategy for Tetrasubstituted Olefin Synthesis Using Vinyl 2-Pyrimidyl Sulfide as a Platform. -A programmable and diversity-oriented, regio-and stereoselective synthetic route for tetra-and triaryl substituted olefins is presented involving a site-selective and sequential assembly of aryl/heteroaryl substituents onto a C=C core of sulfide (I). By changing the addition order of the aryl groups it is possible to prepare all stereo-and regioisomers from a set of aryl groups. -(ITAMI*, K.; MINENO, M.; MURAOKA, N.; YOSHIDA, J.-I.; J.