Tandem Hydroformylation/Acyloin Reaction - The Synergy of Metal Catalysis and Organocatalysis Yielding Acyloins Directly from Olefins
作者:Karoline A. Ostrowski、Thiemo A. Faßbach、Andreas J. Vorholt
DOI:10.1002/adsc.201401031
日期:2015.5.4
A novel, atom efficient, orthogonal tandem catalysis was developed yielding acyloin products (α‐hydroxy ketones) directly from olefins under hydroformylation conditions. The combination of a metal‐catalysed hydroformylation and an organocatalysed acyloin reaction provides three atom efficient CC bond formations to linear, multifunctional molecules via linkage of the intermediate n‐aldehydes. Additionally
Decreasing Side Products and Increasing Selectivity in the Tandem Hydroformylation/Acyloin Reaction
作者:Karoline A. Ostrowski、Thiemo A. Faßbach、Dennis Vogelsang、Andreas J. Vorholt
DOI:10.1002/cctc.201500727
日期:2015.9.1
to a variety of olefins is enabled with comparable excellent selectivities up to >99 % for the first and second reaction step, therefore a general synthesis for the conversion of olefins into acyloins is found. Furthermore, very good to excellent yields for the intermediates and final acyloin products were observed within two catalysed reactions in one preparative step. The acyloin product was applied
A simple and efficient one-pot procedure for the synthesis of α-diketones from aldehydes via benzoin condensation under the influence of a catalytic amount of azolium salt combined with DBU has been developed. Thus, aldehyde was allowed to react with the azolium salt/DBU catalytic system at room temperature, and then the reaction mixture was heated to 70 °C under air atmosphere to afford the corresponding
been studied by dehydrogenation using a range of heterogeneous catalysts under solvent-free conditions at high temperatures (160–180 °C). Dehydrogenation using activated Ru/C under vacuum provided α-hydroxyketone with 93% conversion and 82% GC yield. The optimized conditions were applied to a range of oleochemical diols, including a vegetable oil derivative, to obtain the corresponding α-hydroxyketones
An improved dominohydroformylation/benzoincondensation to give α‐hydroxy ketones has been developed. Easily available olefins are smoothly converted into the corresponding α‐hydroxy ketones in high yields with excellent regioselectivities. Key to success is the use of a specific catalytic system consisting of a rhodium/phosphine complex and the CO2 adduct of an N‐heterocyclic carbene.