Triphenylphosphine → Methyl 3-[5-(dimethylcarbamoyl)pyrazin-2-yl]oxy-5-[(2S)-1-[(2-methylpropan-2-yl) oxy]propan-2-yl]oxy-benzoate

Participants

Reaction Conditions

Reaction Steps

To methyl 3-[5-(dimethylcarbamoyl)pyrazin-2-yl]oxy-5-hydroxy-benzoate (10 g, 32 mmol) was added triphenylphosphine (10.3 g, 39.4 mmol), THF (100 mL) and (2R)-1-[(2-methylpropan-2-yl)oxy]propan-2-ol (CAS no. 136656-73-0) (5.21 g, 39.4 mmol). The resulting slurry was cooled to 0° C. and diethylazodicarboxylate (50% w/v in toluene, 13.7 mL, 39.4 mmol) was charged dropwise keeping the temperature below 10° C. After 2 hours the solvent was evaporated under reduced pressure and taken up with ethyl acetate (23 mL). A solid crashed out which was filtered and the mother liquors were evaporated under reduced pressure, taken up into ethyl acetate (23 mL) and isohexane (53 mL) and the resulting solid filtered, the mother liquors were evaporated under reduced pressure and the resulting residue was purified by flash chromatography eluting with 80% ethyl acetate/ 20% isohexane to afford the product (13.5 g).

Provenance & Evidence