反应详情

In a 100 mL beaker, 1.12 g of 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) was added to a solution of ether (30 mL) and 5 N KOH (2.3 mL) and stirred until N2 evolution ceased. In another beaker, crude 2-methyl-2-phenoxy-3-thiophen-2-yl-propionic acid (1.00 g) was dissolved in CH2Cl2 (20 mL). The beaker containing the ether/base mixture was then placed in a Dewar flask containing dry ice/acetone, the aqueous layer was frozen and the ether layer decanted into the other beaker containing the crude acid solution. This mixture was then stirred for an additional 5 min, which by HPLC showed the reaction to be complete. The solvent was removed in vacuo to provide a crude oil. Purification by flash chromatography EtOAc: hexane (1:10) provided 533 mg of desired product (28%): 1H NMR (400 MHz, CDCl3) • 7.16-7.22 (m, 4H), 6.96 (m, 1H), 6.91 (m, 1H), 6.84 (m, 2H), 3.73 (s, 3H), 3.49 (d, 1H), 3.38 (d, 1H), 1.42 (s, 3H); MS (EI) 277.1 (M+H)+.

1. temperaturethe aqueous layer was frozen
2. customthe ether layer decanted into the other beaker
3. additioncontaining the crude acid solution
4. customthe reaction
5. customThe solvent was removed in vacuo
6. customto provide a crude oil
7. customPurification by flash chromatography EtOAc: hexane (1:10)