Nitrogen → (3S)-8-amino-9,10-difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carbonitrile

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Reaction Steps

To a solution of 4 (500 mg, 1.69 mmol) and triethylamine (1.2 mL, 8.5 mmol.) in DCM (20 mL) was added POCl3 (431 μL, 3.2 mmol.) dropwise under Ar (or N2) at 0° C. Stirring was continued for an additional 5 h. A dark colored mixture was formed. Upon completion of the reaction, DCM was removed under vacuo and the residue was washed several times with water. The solid was dried under vacuum to give 5 (385 mg, 82% yield). This product was not very soluble except in DMF or DMSO and was used in the next step without further purification.

Provenance & Evidence