반응 #54648

반응 방정식

5,6,7,8-tetrahydro-8-oxo-4H-cyclohepta[b]thien-4-ylurea

ethanol

sodium borohydride

→

trans-5,6,7,8-tetrahydro-8-hydroxy-4H-cyclohepta[b]thien-4-ylurea

용매

water

반응 조건

후처리

1. 1
   기타the mixture is evaporated to dryness in vacuo
2. 2
   workup.ADDITIONAcetone is added to the residue
3. 3
   기타the mixture is evaporated to dryness
4. 4
   추출The residue is then extracted with 3×75 ml
5. 5
   기타portions of boiling acetone, the acetone solution being decanted each time
6. 6
   여과The combined acetone solutions are filtered
7. 7
   기타evaporated to dryness
8. 8
   세척The residue is then washed with diethyl ether
9. 9
   기타is crystallized from methanol/ethyl acetate
10. 10
    기타to afford 0.148 g
11. 11
    기타The mother liquor is evaporated to dryness
12. 12
    기타chromatographed on preparative thin-layer silica-gel chromatographic plates with 15 parts methanol/85 parts chloroform
13. 13
    기타A fraction melting at 171°-175° C. is then obtained
14. 14
    기타after separation and recrystallization from methanol/ethyl acetate
15. 15
    기타A second fraction melting at 169°-172° C. is also obtained

실험 절차

A sample of 1.72 g. of 5,6,7,8-tetrahydro-8-oxo-4H-cyclohepta[b]thien-4-ylurea is stirred in 120 ml. of absolute ethanol and 0.5 g. of sodium borohydride is added. After 5.5 hours, 50 ml. of water is added to the mixture and the mixture is evaporated to dryness in vacuo. Acetone is added to the residue and the mixture is evaporated to dryness. The residue is then extracted with 3×75 ml. portions of boiling acetone, the acetone solution being decanted each time. The combined acetone solutions are filtered and evaporated to dryness. The residue is then washed with diethyl ether and the insoluble solid (contains some gum) is crystallized from methanol/ethyl acetate to afford 0.148 g. of yellow solid. The mother liquor is evaporated to dryness and chromatographed on preparative thin-layer silica-gel chromatographic plates with 15 parts methanol/85 parts chloroform. A fraction melting at 171°-175° C. is then obtained after separation and recrystallization from methanol/ethyl acetate. This material analyzes acceptably (carbon, hydrogen and nitrogen) for the title compound and the infrared spectrum also supports the structure. A second fraction melting at 169°-172° C. is also obtained and its infrared spectrum is virtually identical with that of the above-mentioned fraction.

출처