6-Methoxy-5-(1-methyl-1H-pyrazol-4-yl)pyridin-2-ylamine → gamma-Secretase modulator 6

Participants

Reaction Conditions

Reaction Steps

Charged a round-bottom flask with a mixture of 6-methoxy-5-(1-methyl-1H-pyrazol-4-yl)pyridin-2-amine (7.6 g, 37.21 mmol), (R)-8-chloro-4-methyl-2-phenyl-2,3,4,5-tetrahydropyrido[3,2-f][1,4]oxazepine (10.22 g, 37.21 mmol), palladium (II) acetate (0.251 g, 1.12 mmol), rac-BINAP (1.159 g, 1.86 mmol), potassium carbonate (7.71 g, 55.82 mmol), and toluene (150 mL). The atmosphere was inerted through consecutive vacuum-nitrogen purge cycles, then heated at 120 °C for 16 hours. HPLC-UV shows <9% of starting materials remaining. Added an additional 25mg palladium acetate and 116 mg BINAP, then heating was continued for another 2 hours. HPLC-UV does not show any additional progress. The heating block was removed and the mixture was allowed to cool to room temperature. Added 300 mL dichloromethane and adjusted the pH to 2 with 2.0N aqueous HCl. Separated the phases and basified the aqueous with 1.0N aqueous sodium hydroxide. Extracted with 200 mL DCM, followed by a second extraction with 100 mL DCM. The organics were dried with magnesium sulfate and concentrated by rotary evaporator to yield EN04092-38-001 (16.1 g, 36.4 mmol, 98 %) as an amber-coloured foam.

Provenance & Evidence