반응 #52571

반응 방정식

4-methanesulfonyl-2-nitrobenzoyl chloride

acetone cyano-hydrin

4-methylene-3-oxabicyclo[3.2.1]octan-2-one

triethylamine

acetone cyanohydrin

→

4-hydroxy-3-(4-methanesulfonyl-2-nitrobenzoyl)-bicyclo[3.2.1]oct-3-en-2-one

수율 44.9%

용매

ethyl acetate

acetonitrile

반응 조건

후처리

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITis continued for a further 30 minutes until conversion
3. 3
   추출extracted at a pH value of 13 against water
4. 4
   추출extracted with fresh ethyl acetate, once at pH 5 and once at pH 4
5. 5
   기타dried
6. 6
   농축concentrated by evaporation

실험 절차

2.76 g (0.02 mol) of 93% 4-methylene-3-oxabicyclo[3.2.1]octan-2-one and 4.45 g (0.044 mmol) of triethylamine are stirred for 6 hours at a temperature of 20° C. in 50 ml of acetonitrile in the presence of 170 mg (2 mmol) of acetone cyanohydrin. 4.22 g (0.16 mol) of 4-methanesulfonyl-2-nitrobenzoyl chloride are then introduced and stirring is continued for a further 12 hours at a temperature of 20° C. A further 170 mg (2 mmol) of acetone cyano-hydrin are then added and stirring is continued for a further 30 minutes until conversion is complete. The reaction mixture is then taken up in ethyl acetate and extracted at a pH value of 13 against water. The aqueous phase is acidifed and extracted with fresh ethyl acetate, once at pH 5 and once at pH 4, dried and concentrated by evaporation. 3.05 g of 4-hydroxy-3-(4-methanesulfonyl-2-nitrobenzoyl)-bicyclo[3.2.1]oct-3-en-2-one with a good level of purity are obtained. The yield is 44.9% based on the starting material 4-methylene-3-oxa-bicyclo[3.2.1]octan-2-one or 52.2% based on the starting material 4-methanesulfonyl-2-nitrobenzoic acid.

출처