70432-50-7Relevant articles and documents
An efficient method for retro-Claisen-type C-C bond cleavage of diketones with tropylium catalyst
Hussein,Huynh,Hommelsheim,Koenigs,Nguyen
supporting information, p. 12970 - 12973 (2018/11/23)
The retro-Claisen reaction is frequently used in organic synthesis to access ester derivatives from 1,3-dicarbonyl precursors. The C-C bond cleavage in this reaction is usually promoted by a number of transition-metal Lewis acid catalysts or organic Br?nsted acids/bases. Herein we report a new convenient and efficient method utilizing the tropylium ion as a mild and environmentally friendly organocatalyst to mediate retro-Claisen-type reactions. Using this method, a range of synthetically valuable substances can be accessed via solvolysis of 1,3-dicarbonyl compounds.
Alcohol dehydrogenase-catalyzed synthesis of enantiomerically pure δ-lactones as versatile intermediates for natural product synthesis
Fischer, Thomas,Pietruszka, Joerg
, p. 2521 - 2530,10 (2020/08/31)
Starting from ethyl 4-bromobutyrate, the chemoenzymatic synthesis of 6-vinyl-tetrahydro-pyran-2-one has been accomplished. A screening of a number of available alcohol dehydrogenases and intense optimization of reaction parameters enabled us to establish an efficient synthesis of either enantiomer of the vinyllactone with excellent enantiomeric excess (>99%). The scope of possible applications of enantiopure vinyllactones has been verified by subjection to cross-metathesis resulting in the total synthesis of the insect pheromone (S)-5-hexadecanolide and the cytotoxic styryllactone goniothalamine as well as derivatives thereof. Copyright
