反应详情

A mixture of 4-(4-chloro-2-fluorophenoxy)phenol (2.23 g; 0.01 mole), the methanesulfonate of S methyl lactate (18.22 g; 0.1 mole, minimum of 90% optical purity), and potassium carbonate (1.4 g; 0.01 mole) in DMSO (75 ml) was stirred at room temperature for 18 hours. After this period, the mixture was poured into water (500 ml) then extracted into ether (3×100 ml). The ether extracts were dried (MgSO4), and the solvent evaporated. The residue was purified by preparative HPLC using 8:2 hexane-ethylacetate as the eluent. The first peak to elute (after the solvent front) was collected and the solvent evaporated. This gave 2.3 g (17%) of a light yellow oil whose 1H and 19F NMR (CDCl3) were consistent with the assigned structure. This material possessed an optical rotation of +24.68° as measured at 25° C. The refractive index was 1.5466. Attempts to measure the optical purity using the optically active NMR shift reagent tris-[3-(trifluoromethylhydroxymethylene)-d-camphorateo]europium (III) were not successful. Based upon the optical purity of the starting lactate the optical purity is estimated to be between 75 and 95%.

1. waitAfter this period
2. extractionthen extracted into ether (3×100 ml)
3. dry with materialThe ether extracts were dried (MgSO4)
4. customthe solvent evaporated
5. customThe residue was purified by preparative HPLC
6. washThe first peak to elute (after the solvent front)
7. customwas collected
8. customthe solvent evaporated
9. customan optical rotation of +24.68°
10. customas measured at 25° C