Water → Ethyl 4-chloro-2-(methylthio)-5-oxo-8-phenyl-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidine-6-carboxylate

To an ice-cooled solution of ethyl 4-chloro-6-((3-ethoxy-3-oxopropyl)(phenyl)amino)-2-(methylthio)pyrimidine-5-carboxylate (23.0 g, 54.25 mmol) in tetrahydrofuran (400 mL), LDA [generated at 0° C. using diisopropylamine (25.37 mL, 179.4 mmol) and n-BuLi (74.2 mL, 173.9 mmol) in tetrahydrofuran (300 mL)] was added dropwise. The reaction mixture was further stirred for additional 1 h and water (500 mL) was added to the reaction mixture. The organic layer was separated and the aqueous layer was extracted using EtOAc (200 mL×2). The combined organic layer was washed with water (500 mL) and brine (500 mL); dried over anhydrous sodium sulphate and concentrated under reduced pressure to give crude product. Crude product from two batches of the same size were combined and purified by silica gel column chromatography (polarity) to provide ethyl 4-chloro-2-(methylthio)-5-oxo-8-phenyl-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidine-6-carboxylate (21 g, 51.2% yield). 1H NMR (400 MHz, CDCl3): δ 7.48-7.43 (m, 2H), 7.37-7.28 (m, 3H), 4.37 (dd, J=7.2, 13.6 Hz, 1H), 4.27 (q, J=7.2 Hz, 2H), 4.11 (dd, J=4.8, 13.6 Hz, 1H), 3.75 (dd, J=4.8, 7.2 Hz, 1H), 2.17 (s, 3H), 1.29 (t, J=7.2 Hz, 3H). LCMS [M+H]: 378

1. additionwas added dropwise
2. customThe organic layer was separated
3. extractionthe aqueous layer was extracted
4. washThe combined organic layer was washed with water (500 mL) and brine (500 mL)
5. dry with materialdried over anhydrous sodium sulphate
6. concentrationconcentrated under reduced pressure
7. customto give crude product
8. custompurified by silica gel column chromatography (polarity)

ORD-Eintrag

ord-5abf271ba4244136bbb394ae485b953c

Quelldatensatz

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08343983B2