Palladium-Catalyzed Stereoselective Synthesis of (E)-Stilbenes via Organozinc Reagents and Carbonyl Compounds
作者:Jin-Xian Wang、Kehu Wang、Lianbiao Zhao、Hongxia Li、Ying Fu、Yulai Hu
DOI:10.1002/adsc.200606016
日期:——
In the presence of a catalytic amount of PdCl2(PPh3)2 and a silylating agent, organozinc halides reacted with carbonylcompounds to give the corresponding (E)-stilbenes in good to excellent yields under mild conditions. The reaction mechanism is briefly discussed.
3,6,8-tetrabromopyrene with 4-[(–)-β-citronellyloxy]phenylethyne was employed to synthesize 1,3,6,8-tetra[4-(citronellyloxy)phenylethynyl]pyrene. The pyrene derivative catalyzed the reductive desulfonylation of ethenyl sulfones via visible-light irradiation (514 nm green light-emitting diodes) in the presence of i-Pr2NEt. The β-citronellyloxy groups provided the sufficient solubility to the highly
N-graphitic-modified cobalt nanoparticles (Co/[email protected]2-800) are shown to be active in the semihydrogenation of alkynes to alkenes. Key to success for efficient catalysis is both the modification of the metal nanoparticles by nitrogen-doped graphitic layers and the use of silica as support. Several internal alkynes are converted to the Z isomer in high yields with up to 93% selectivity. In addition, a
Stereocontrolled synthesis of (E)-stilbene derivatives by palladium-catalyzed Suzuki-Miyaura cross-coupling reaction
作者:Hailee H. Rau、Nathan S. Werner
DOI:10.1016/j.bmcl.2018.04.004
日期:2018.9
stereocontrolled synthesis of (E)-stilbene derivatives by palladium-catalyzed Suzuki-Miyauracross-couplingreaction of (E)-2-phenylethenylboronic acid pinacol ester with aryl bromides was investigated. (E)-2-Phenylethenylboronic acid pinacol ester was prepared by 9-BBN-catalyzed hydroboration of phenylacetylene with pinacolborane. This reagent undergoes facile palladium-catalyzed cross-coupling with a diverse
New water-soluble palladium(II) iodide complexes derived from N-protonated or N-alkyl-1,3,5-triaza-7-phosphaadamantanes: Synthesis, crystal structure and catalytic properties in aqua media
salts [PTA-R]I (R = H, Me, Et, nPr, nBu) give the water-soluble palladium(II) complexes of type [PdI3(PTA-R)] in isolated yields of 62–81%. All these compounds have been fully characterized by IR and NMR spectroscopies and elemental analyses. Their molecular structures were confirmed by single crystal X-ray diffraction analysis. The complexes belong to the relatively unusual zwitterionic, coordination