6-(4-Chloro-3-trifluoromethyl-phenoxy)-2-methyl-5-trimethylsilanylethynyl-pyridin-3-ylamine → 6-(4-Chloro-3-trifluoromethyl-phenoxy)-5-ethynyl-2-methyl-pyridin-3-ylamine

Participants

Reaction Steps

In a 50 ml single-necked round-bottomed flask equipped with a condensor, 35 mg of 2-(4-chloro-3-trifluoromethyl-phenoxy)-6-methyl-5-nitro-3-trimethylsilanylethynyl-pyridine is stirred in 0.50 ml of methanol. Under cooling with an ice/water bath, 0.50 ml of concentrated aqueous HCl is added dropwise by syringe (some precipitation is observed). The ice bath is removed and 77 mg of anhydrous SnCl2 is added in portions. Stirring is continued under heating to reflux for 2 h. After cooling the mixture to ambient temperature, it is concentrated in vacuo to give a brown solid. After adding AcOEt, 5 ml of 4 M aqueous NaOH solution is added (pH 12). Following extraction, the AcOEt phase is dried over Na2SO4, filtered and the solvent removed in vacuo to give 30 mg a brown oil. Purification was done by flash chromatography [silica gel cartridge (5 g, 20 ml) with heptane/ethyl acetate 3:1 (v:v)] to give 7 mg of a 1. fraction (6-(4-chloro-3-trifluoromethyl-phenoxy)-2-methyl-5-trimethylsilanylethynyl-pyridin-3-ylamine) and 15 mg of a 2. fraction of the compound as a brown solid. RP HPLC: Retention time of compound: 1.87 minutes.

Provenance & Evidence