Palladium(0)-catalyzed allylation of highly acidic and non-nucleophilic arenesulfonamides, sulfamide, and cyanamide. II. Formation of medium and large heterocycles
Arenesulfonamides 10, cyanamide 29, and sulfamide 32 react with allylic bis-carbonates 8 (Z and E) and 9 under Pd(0)-catalysis to afford medium and large unsaturated heterocycles instead of three and/or five-membered ring compounds. Stable 15-membered palladium-containing rings were also isolated from arenesulfonamides and 8, with three trans olefinic systems coordinated to the metal. NMR and MALDI-TOF
The synthesis of 1,2- and 1,3-diols and derivatives has been achieved from ω-hydroxy π-allyl palladium complexes by using boric acid and trialkyl borates.
N-aryl-4-vinyloxazolidin-2-ones. The success of the reaction depends on the acidity of the aniline and requires in situ conversion of the dicarbonate into carbamate carbonate by nucleophilicattack of the aniline conjugate base followed by palladium-catalyzed intramolecular cyclization.
A highly enantioselectiveallylic substitution of (Z)-but-2-ene-1,4-diol derivatives was developed using a rhodium(I) catalyst and arylboronic acids as nucleophiles. The reaction yields versatile homoallylicalcohols from readily available linear biscarbonates. homoallylicalcohols - rhodium - boronic acids - desymmetrization - asymmetric allylic substitution