Equilibria among anions of .alpha.-hydroxy .beta.-diketones and .alpha.-ketol esters

Enzymatic diastereo- and enantioselective synthesis of α-alkyl-α,β-dihydroxyketones

“…However, this outcome can be exploited as a method for the kinetic resolution of 2/3 regioisomeric mixtures, though the recovery by chromatography of symmetric diketones 3b-d was complicated by their intrinsic instability on silica. 20 The enzymatic reduction of pure diketone 2e proceeded smoothly in 5 h furnishing the diol 4e in a 63% yield with high stereoselectivity (entry 5). By contrast, no reduction product was obtained with symmetric diketone 2f (entry 6).…”

A carbonate-forming Baeyer-Villiger monooxygenase

“…31 ). Epoxide opening facilitated by abstraction of C18 α-proton leads to an a-alcohol intermediate, which can form the epoxy alkoxide 20 and readily rearrange across the 1,5 diketone system to afford 9 . This last step is analogous to the reported Lewis-acid-promoted conversion of an α-hydroxy β-dicarbonyl compound to a carbonate 21 , 22 .…”

The first perfluoroacetylacetonate metal complexes: as unexpectedly robust as tricky to makeElectronic supplementary information (ESI) available: details of the preparation of the complexes, analytical, NMR spectroscopical, and crystallographic data. See: http://www.rsc.org/suppdata/cc/b1/b111249j/

“…The difference is believed to be due to facile S N -type hydrolysis of the central C-F bond, likely aided by pre-coordination of the Ln 3+ electrophile to an O atom of acac-F 7 H before chelation. The resulting carbinol (CF 3 C(O)) 2 CHOH then rearranges 8 to CF 3 COO-CH 2 C(O)CF 3 which is hydrolyzed to CF 3 COO 2 . However, once acac-F 7 is h 2 -coordinated, nucleophilic attack of water or OH 2 on the central carbon is impeded for both steric and electronic reasons.…”