Реакция #1470366

Уравнение реакции

methanesulfonate

methyl lactate

potassium carbonate

4-(4-chloro-2-fluorophenoxy)phenol

→

2-[4-(4-chloro-2-fluorophenoxy)phenoxy]propionic acid, methyl ester

Растворители

water

DMSO

Условия реакции

Обработка

1. 1
   workup.WAITAfter this period
2. 2
   Экстракцияthen extracted into ether (3×100 ml)
3. 3
   СушкаThe ether extracts were dried (MgSO4)
4. 4
   Другоеthe solvent evaporated
5. 5
   ДругоеThe residue was purified by preparative HPLC
6. 6
   ПромывкаThe first peak to elute (after the solvent front)
7. 7
   Другоеwas collected
8. 8
   Другоеthe solvent evaporated
9. 9
   Другоеan optical rotation of +24.68°
10. 10
    Другоеas measured at 25° C

Методика

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%.

Источник