A reaction of α-bromo aromatic ketones in water with microwave irradiation gave the corresponding α-hydroxy aromatic ketones in good yields. The use of microwaves was found to significantly improve yields and shorte...A reaction of α-bromo aromatic ketones in water with microwave irradiation gave the corresponding α-hydroxy aromatic ketones in good yields. The use of microwaves was found to significantly improve yields and shorten the reaction time. This reaction afforded a very clean, convenient method for the synthesis of α-hydroxy aromatic ketones.展开更多
α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemis...α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemistry.In this paper a simpler Mosher′s method was developed from the modified Mosher′s method.It only need one configuration of MTPA to determine the absolute configurations of four α-hydroxy ketones with their(S)-and(R)-MTPA esters using()1H NMR.The signals of protons on the same side with phenyl ring will be in the higher field than those of on the different side ones.Consequently according to the model the main configuration of compounds 1,2,3 and 4 were determined as S,R,R and S, respectively.展开更多
1 Results Biotransformations are enzyme- and whole cell-catalysed conversions of non-natural substrates to products.They are important tools in organic synthesis,especially for the syntheses of chiral molecules,where ...1 Results Biotransformations are enzyme- and whole cell-catalysed conversions of non-natural substrates to products.They are important tools in organic synthesis,especially for the syntheses of chiral molecules,where the reactions catalysed may be asymmetric syntheses or the resolution of racemates.The main advantages associated with the use of single enantiomer compounds are increased specificity and the avoidance of adverse side effects[1].Whole cell reactions are advantegous over enzyme-catalyzed rea...展开更多
基金financially supported by the National Special Fund for State Key Laboratory of Bioreactor Engineering(No.2060204)the National Natural Science Foundation of China(No.20672037)
文摘A reaction of α-bromo aromatic ketones in water with microwave irradiation gave the corresponding α-hydroxy aromatic ketones in good yields. The use of microwaves was found to significantly improve yields and shorten the reaction time. This reaction afforded a very clean, convenient method for the synthesis of α-hydroxy aromatic ketones.
文摘α-Hydroxy ketones are frequently involved in biologically important compounds and,therefore,the determination of the stereochemistry of these structural elements has attracted the attention in natural products chemistry.In this paper a simpler Mosher′s method was developed from the modified Mosher′s method.It only need one configuration of MTPA to determine the absolute configurations of four α-hydroxy ketones with their(S)-and(R)-MTPA esters using()1H NMR.The signals of protons on the same side with phenyl ring will be in the higher field than those of on the different side ones.Consequently according to the model the main configuration of compounds 1,2,3 and 4 were determined as S,R,R and S, respectively.
文摘1 Results Biotransformations are enzyme- and whole cell-catalysed conversions of non-natural substrates to products.They are important tools in organic synthesis,especially for the syntheses of chiral molecules,where the reactions catalysed may be asymmetric syntheses or the resolution of racemates.The main advantages associated with the use of single enantiomer compounds are increased specificity and the avoidance of adverse side effects[1].Whole cell reactions are advantegous over enzyme-catalyzed rea...