3-Methylbutanal → 3-(3-(tert-butyldimethylsilyloxy)propyl)-6-chloro-5-(1-hydroxy-3-methylbutyl)-1-methylpyrido[3,4-d]pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(3-(tert-butyldimethylsilyloxy)propyl)-6-chloro-1-methylpyrido[3,4-d]pyrimidine-2,4(1H,3H)-dione (See Compound 49, step 3, 1.149 g, 3 mmol) in THF (30 mL) at −78° C. was added LDA (2M in THF, 7.5 mL, 15 mmol) dropwise. The reaction was stirred at −78° C. for 30 min then 3-methylbutanal (516 mg, 6 mmol) in THF (5 mL) was added dropwise. The reaction was stirred at −78° C. for 20 min, quenched with aq. NH4Cl (5 mL) then diluted with EA (15 mL) and water (5 mL). The organic layer was washed with brine (20 mL), dried over Na2SO4 and concentrated to a residue which was purified by chromatography eluted with PE/EA (2:1) to give 3-(3-(tert-butyldimethylsilyloxy)propyl)-6-chloro-5-(1-hydroxy-3-methylbutyl)-1-methylpyrido[3,4-d]pyrimidine-2,4(1H,3H)-dione (464 mg, 30% yield) as a white solid. LCMS: MH+ 470 and TR=2.198 min.

Provenance & Evidence