tert-butyl 6-nitro-1H-indazole-1-carboxylate synthesis

Yield:219503-74-9 99%

Reaction Conditions:

Stage #1: 6-nitroindazolewith sodium hydrogencarbonate in tetrahydrofuran at 0; for 0.5 h;
Stage #2: di-tert-butyl dicarbonate in tetrahydrofuran at 20; for 2 h;

Steps:

4.1.4. General procedure for Boc-protection

General procedure: Procedure C: NaHCO₃ (3.3 equiv) was added to the solution of the amine (1 equiv) at 0°C, stirred for 30 min, and then di-tert-butyl dicarbonate (1.1 equiv) was added to the reaction mixture. The reaction was continued at room temperature for 2 h and then diluted with ethyl acetate. It was washed with H₂O and then with brine. Finally, it was dried over MgSO₄, concentrated, and purified by column chromatography to give the desired product.

References:

Lee, Jeewoo;Tran, Phuong-Thao;Hoang, Van-Hai;Thorat, Shivaji A.;Kim, Sung Eun;Ann, Jihyae;Chang, Yu Jin;Nam, Dong Woo;Song, Hyundong;Mook-Jung, Inhee;Lee, Jiyoun [Bioorganic and Medicinal Chemistry,2013,vol. 21,# 13,p. 3821 - 3830]