t-Butyl bromide → Tert-butyl 1-[8-methoxy-5-(1-oxo-3H-isobenzofuran-5-yl)-[1,2,4]triazolo[1,5-a]pyridin-2-yl]cyclopropanecarboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A suspension of 1-[8-methoxy-5-(1-oxo-3H-isobenzofuran-5-yl)-[1,2,4]triazolo[1,5-a]pyridin-2-yl]cyclopropanecarboxylic acid (30 mg, 83 μmol) and benzyltriethyl-ammonium chloride (19 mg, 83 μmol) in DMF (1.0 mL) was gently heated until it became a solution. Tert-butyl bromide (297 μL, 2.64 mmol) and K2CO3 (171 mg, 1.24 mmol) were added and the mixture was stirred at 55° C. for three days. Additional tert-butyl bromide (139 μL, 1.24 mmol) and K2CO3 (171 mg, 1.24 mmol) were added and the mixture was stirred at 55° C. for one more day. PrepHPLC purification afforded the title compound. HPLC-Retention time (XE Metode 7 CM): 2.29 minutes. Detected “M+1”-mass: 422.18. Calculated “M+1”-mass: 422.17. 1H NMR (DMSO, 300 MHz): δ=8.27-8.22 (m, 1H), 8.16 (dd, 1H, 3=8.0, 1.5 Hz), 8.00 (d, 1H, J=8.2 Hz), 7.40 (d, 1H, J=8.2 Hz), 7.22 (d, 1H, J=8.3 Hz), 5.51 (s, 2H), 4.04 (s, 3H), 1.54-1.40 (m, 4H), 1.38 (s, 9H) ppm.

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