Acetic Acid → HCID 18937647, compound

Participants

Reaction Steps

To a solution of diisopropylamine (0.11 ml, 0.82 mmole) in tetrahydrofuran (2 ml) at -78° C. was added under the argon atmosphere 1.5N butyllithium (0.51 ml, 0.77 mmole), and the mixture was stirred for 30 minutes. Next, to this reaction mixture were added ethyl propiolate (93 μl, 0.92 mmole) followed by a solution of 2-nitro-4-(p-toluoylamino)-benzaldehyde (144.5 mg, 0.51 mmole), and the mixture was further stirred at -78° C. for 1 hour. After a solution of acetic acid (90 μl, 1.58 mmole) in tetrahydrofuran (1 ml) was added to the reaction mixture, it was extracted with ethyl acetate. The organic layer was washed with dilute hydrochloric acid, water, a saturated aqueous sodium hydrogen carbonate solution, and a saturated aqueous saline in this sequence. After the organic layer was dried over anhydrous magnesium sulfate, the solvent was removed under reduced pressure to give ethyl 4-hydroxy-4-(2-nitro-4-(p-toluoylamino)-phenyl)-2-butynoate as an oil (176 mg). The product thus obtained was dissolved in toluene (2 ml), 4-methoxybenzylazide (250 mg, 1.53 mmole), and the mixture was stirred with heating at 100° C for 5 hours. The reaction mixture was cooled to room temperature, the resulting crystalline products were filtered to give the 1 : 1 mixture of ethyl 4-(hydroxy-(2-nitro-4-(p-toluoylamino)phenyl)methyl)-1-(4- methoxybenzyl)-1,2,3-triazole-5-carboxylate (a-i) and ethyl 5-(hydroxy-(2-nitro-4-(p-toluoylamino)phenyl)methyl)-1-(4-methoxybenzyl)-1,2,3-triazole-4-carboxylate (a-2) (103.4 mg, 37%).

Provenance & Evidence