反应详情

A dispersion of sodium hydride in a mineral oil (60%) (0.22 mol) was treated with hexane under N2 flow to remove the oil and then dispensed in THF (100 ml) under N2 flow. Ethyl (diethylphosphono)acetate (0.22 mol) was added dropwise. The mixture was stirred for 30 minutes until the gas development has stopped. A mixture of (1,1′-biphenyl)-4-ylphenylmethanone (0.2 mol) in THF (100 ml) was added dropwise at room temperature. The mixture was stirred at room temperature for 1 hour, then stirred and refluxed for 17 hours, cooled, poured out into HCl 10% and ice and extracted three times with DCM. The combined organic layer was washed once with a saturated K2CO3 solution, twice with H2O and once with a saturated NaCl solution, then dried, filtered and the solvent was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2/EtOAc/hexane 1/1/98). Two pure fractions were collected and their solvents were evaporated. Fraction 2 was crystallized from 2-propanol. The precipitate was filtered off and dried. The mother layer was evaporated and combined with fraction 1, yielding 45 g of ethyl 3-[(1,1′-biphenyl)4-yl]-3-phenyl-2-propenoate (interm. 18).

1. customto remove the oil
2. additionwas added dropwise at room temperature
3. stirringThe mixture was stirred at room temperature for 1 hour
4. stirringstirred
5. temperaturerefluxed for 17 hours
6. temperaturecooled
7. extractionextracted three times with DCM
8. washThe combined organic layer was washed once with a saturated K2CO3 solution, twice with H2O and once with a saturated NaCl solution
9. customdried
10. filtrationfiltered
11. customthe solvent was evaporated
12. customThe residue was purified by column chromatography over silica gel (eluent: CH2Cl2/EtOAc/hexane 1/1/98)
13. customTwo pure fractions were collected
14. customtheir solvents were evaporated
15. customFraction 2 was crystallized from 2-propanol
16. filtrationThe precipitate was filtered off
17. customdried
18. customThe mother layer was evaporated