4-Methylmorpholine → 5-amino-2-(2,6-difluorophenyl)-N-(1-methyl-5-(5-methyl-5-((2,2,2-trifluoroacetamido)methyl)-1,3-dioxan-2-yl)-1H-pyrazol-4-yl)thiazole-4-carboxamide

Participants

Reaction Steps

2,2,2-trifluoro-N-((5-methyl-2-(1-methyl-4-nitro-1H-pyrazol-5-yl)-1,3-dioxan-5-yl)methyl)acetamide (171 mg, 0.49 mmol, intermediate 84) was dissolved in MeOH (30 mL) and ammonium formate (170 mg, 2.69 mmol) and 10% Pd/C (140 mg, 0.13 mmol) were added. The mixture was heated at reflux for 18 hr before being cooled to room temperature. The suspension was filtered, the cake washed with EtOAc (100 mL) and the filtrate concentrated under reduced pressure. The crude residue was dissolved in EtOAc (10 mL) and 5-amino-2-(2,6-difluorophenyl)thiazole-4-carboxylic acid (131 mg, 0.51 mmol) was then added followed by N-methylmorpholine (0.11 mL, 1.46 mmol). Propylphosphonic anhydride solution (50% wt in EtOAc, 338 mg, 0.53 mmol) was added dropwise and the reaction mixture was stirred at room temperature for 16 hr. The reaction mixture was concentrated under reduced pressure and purified via silica gel chromatography (0-5% 7 N NH3 in MeOH/DCM) to give 5-amino-2-(2,6-difluorophenyl)-N-(1-methyl-5-(5-methyl-5-((2,2,2-trifluoroacetamido)methyl)-1,3-dioxan-2-yl)-1H-pyrazol-4-yl)thiazole-4-carboxamide as a white solid (102 mg, 18% over three steps). A mixture of 5-amino-2-(2,6-difluorophenyl)-N-(1-methyl-5-(5-methyl-5-((2,2,2-trifluoroacetamido)methyl)-1,3-dioxan-2-yl)-1H-pyrazol-4-yl)thiazole-4-carboxamide (101 mg, 0.18 mmol) in MeOH (6 mL) and aqueous saturated K2CO3 solution (0.6 mL) was heated in a microwave at 100° C. for 1 hr. The reaction mixture was cooled to room temperature, concentrated under reduced pressure and purified via silica gel chromatography (0-20% MeOH/DCM) to give 175 as a white solid (4 mg, 5%). 1H NMR (400 MHz, CDCl3) δ 9.80 (s, 1H), 8.24 (s, 1H), 7.34-7.27 (m, 1H), 7.05-6.97 (m, 2H), 6.15 (s, 2H), 5.70 (s, 1H), 3.98-3.91 (m, 2H), 3.86 (s, 3H), 3.80 (d, J=11.0 Hz, 2H), 2.54 (s, 2H), 1.26 (s, 3H). Alkyl NH2 not observed. LCMS (ES+) m/z 465 (M+1).

Provenance & Evidence