Ligand-Free Palladium-Catalyzed Oxyarylation of Dihydronaphthal­enes and Chromenequinone with o-Iodophenols and 3-Iodolawsone in PEG-400: An Efficient Synthesis of 5-Carbapterocarpans and Pterocarpanquinones

Dihydronaphthalenes were oxyarylated with o-iodophenols, in PEG-400 at 140 or 170 °C, leading regio- and stereoselectively to 5-carbapterocarpans. By using Pd(OAc)2 (5–10 mol%) as precatalyst and Ag2CO3 (1.1 equiv) as base (conditions A), products were obtained in good to excellent chemical yields, in 5–30 minutes, irrespective of the pattern of substitution the starting materials. Alternatively, when p-hydroxyacetophenone oxime derived palladacycle (1 mol%) was used as precatalyst, and dicyclohexylamine (2 equiv) was used as base (silver-free, conditions B), the corresponding adducts were obtained in moderate to good yields, in 0.5 to 4 hours. Finally, the oxyarylation of dihydronaphthalenes­ and chromenquinone with o-iodophenols and 3-iodolawsone in PEG-400 under conditions A led regio- and stereoselectively to the formation of carbapterocarpanquinones and pterocarpanquinones in moderate yield.Financial support from Brazilian agencies CAPES-DGU (Project 200/09), CNPq, FAPERJ and UFRJ are acknowledged. Spanish MICINN (Projects PHB2008-0037-PC, CTQ2007-62771/BQU, CTQ2010-20387, Consolider INGENIO 2010 CSD2007-00006), FEDER, Generalitat Valenciana (Project PROMETEO/2009/038), and the University of Alicante are acknowledged

New Palladacycle-Derived Acylhydrazones as Pre-catalysts in Mirozoki-Heck Coupling and Oxyarylations

ABSTRACT New acylhydrazone-based palladacycles are prepared and evaluated as pre-catalysts in Mirozoki-Heck and oxyarylation reactions

Continuous-flow CvFAP photodecarboxylation of palmitic acid under environmentally friendly conditions

The fatty acid photodecarboxylase from Chlorella variabilis NC64A (CvFAP) promotes the elimination of CO2 from fatty acids (Cn) producing the corresponding hydrocarbon (Cn-1). Therefore, this enzyme is of great biotechnological interest since it can be used in alternative biofuel production routes matching the concept of green chemistry. However, due to its recent discovery, this reaction still requires optimizations, which was the focus of the present work together with the application of continuous flow system. The results in batch reactors showed the importance of using high power LED lamps (300 W) to reduce the reaction time for full conversion (30 min, >99%). In another approach, a continuous flow system demonstrated high potential, as it enabled full conversion with a half concentration of enzyme extract in a very short residence time of 15 min. Furthermore, the use of less expensive and sustainable light sources, not previously reported for reactions with CvFAP, were evaluated with full conversion (>99%) after 1 h for continuous flow reactions using 300 W common white LED lamp and based preliminary batch reactions investigations using direct sunlight. Thus, important advances and new perspectives for CvFAP photodecarboxylation reactions could be achieved with the present report.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.BT/Biocatalysi

Synthesis and characterization of a magnetic hybrid catalyst containing lipase and palladium and its application on the dynamic kinetic resolution of amines

International audienc

Konkurenční analýza stavebního spoření

Seznámení s problematikou stavebního spoření a jeho využití při řešení bytové situace. Porovnání současných podmínek s podmínkami platnými do 31.12.2003. Zhodnocení dané problematiky u jednotlivých staveních spořitelen. Zhodnocení SS do budoucna a jeho dopady do státního rozpočtu