hydroxylationhypervalent iodineketonesmicrowaveThe alpha-hydroxyketone moiety is commonly found in a wide variety of naturally occurring biologically active substances.This moiety is also served as a very useful intermediate in a number of important organic transformations.Of the various synthetic approaches ...
Direct Proline-Catalyzed Asymmetricα-Aminoxylation of Ketones Nitrosobenzene is the oxygen source in the direct catalytic enantioselective -aminoxylation of ketones catalyzed by L-proline [Eq. (1)]. Versatile -aminoxy... Yujiro,Hayashi,Junichiro,... - 《Angewandte Chemie International Edition》...
However, the addition of HCN to a carbonyl group is reversible, and for diaromatic ketones, the position of equilibrium is towards the carbonyl compound and HCN. In many cases, an advantageous procedure involves first forming the bisulfite adduct of the carbonyl compound and then reacting this ...
Thus hydroxylation of long chain esters or amides can result in preparatively useful product yields (equation 2).3 However simple alkanes, alcohols, halides or ethers as substrates can result in significant competitive α-oxidation at one or both ends of the carbon chain, to give primary ...
7 alpha-hydroxylation of 27-hydroxycholesterol: biologic role in the regulation of cholesterol synthesis. The report of a novel cytochrome P450 enzyme in mouse hippocampus (cyp7b) with close homology to cholesterol 7 alpha-hydroxylase led us to determine the su... KO Martin,AB Reiss,R Lathe,....
[1] 1 is a schematic flowchart of a process for bioconversion of a canrenone or canrenone derivative to a corresponding 11α-hydroxy compound.[2] FIG. 2 is a schematic flowchart of a preferred process for bioconversion of canrenones and canrenone derivatives by 11α-hydroxylation.[3] 3 is ...
As a result of the potential to generate epoxy ketones in both high yield and ee, coupled with the practicalities of the reaction, the Juliá–Colonna reaction has consequently received much interest. A range of substrates have been investigated based on the original procedures by a variety of ...
Poly{[4-(hydroxy)(tosyloxy)iodo]styrene} was efficient in the alpha-hydroxylation reaction of ketones to afford alpha-hydroxyketones in dimethyl sulfoxide-water. The polymer reagent could be regenerated and reused.Wan DBChen JMJournal of Chemical Research. Synopses...
B GEVIG A,SUND N H,C RDOVA A.Direct catalytic enantioselectiveα-aminoxylation of ketones:a stereoselectivesynthesis ofα-hydroxy andα,α’’-dihydroxy ketones. Angewandte Chemie International Edition . 2004Anders B?gevig , Henrik Sunden, Armando Cordova. Direct catalytic enantioselective α -...
The surprising feature is that the yields are quite high for the 11α-hydroxylation of 6,6-difluorosteroids whereas 11β-hydroxylation is very low. Conversion of the 16α ,17α-hydroxyls to acetals, e.g., acetonide, with the ketones mentioned above takes place with an acid catalyst (...