resumo
Tetracarbonylmolybdenum(0) complexes of the type cis-[Mo(CO)(4)(L)] containing chiral 7-(1-pyrindanyl) amine ligands were prepared and found to be effective precatalysts for the epoxidation of achiral (cis-cyclooctene) and prochiral (DL-limonene and trans-beta-methylstyrene) olefins at 55 degrees C. Epoxides were the only products formed from cis-cyclooctene (100% yield) and trans-b-methylstyrene (100% selectivity at 82-85% conversion), and the main products formed from DL-limonene (80-82% 1,2-epoxide selectivity at 85% conversion). Characterization of recovered catalysts revealed that the precatalysts were transformed in situ to stable polyoxomolybdate salts containing the beta-octamolybdate anion [beta-Mo8O26](4-), which was responsible for the catalytic reaction. (c) 2018 Elsevier B.V. All rights reserved.
palavras-chave
ALTERNATING COPOLYMERIZATION; HYDROGEN-PEROXIDE; HYBRID MATERIALS; MOLYBDENUM; LIMONENE; OCTAMOLYBDATE; CARBONYL; PRECURSORS; ALCOHOL; ROUTE
categoria
Chemistry
autores
Neves, P; Nogueira, LS; Valente, AA; Pillinger, M; Goncalves, IS; Sampaio-Dias, IE; Sousa, CAD; Rizzo-Aguiar, F; Rodriguez-Borges, JE
nossos autores
agradecimentos
This work was developed in the scope of the project (Associate Laboratory) CICECO-Aveiro Institute of Materials-POCI-01-0145-FEDER-007679 [FCT (Fundacao para a Ciencia e a Tecnologia) ref. UID/CTM/50011/2013], financed by national funds through the FCT/MEC and when applicable co-financed by FEDER (Fundo Europeu de Desenvolvimento Regional) under the PT2020 Partnership Agreement. The FCT and the European Union are acknowledged for Ph.D. grants to L.N. (PD/BD/109666/2015) and I.E.S-D. (SFRH/BD/93632/2013), and post-doctoral grants to P.N. (SFRH/BPD/110530/2015) and C.A.D.S. (SFRH/BPD/80100/2011) co-funded by MCTES and the European Social Fund through the program POPH of QREN.