3-Oxo-azetidine-1-carboxylic acid tert-butyl ester → tert-butyl 3-((2-chloro-9-methyl-6-morpholino-9H-purin-8-yl)methylene)azetidine-1-carboxylate

Participants

Reaction Steps

To a cold (−78° C.) suspension of dimethyl (2-chloro-9-methyl-6-morpholino-9H-purin-8-yl)methylphosphonate (1.1 g, 2.9 mmol) in THF (26 mL) was added a 2.0M solution of LDA in THF (1.6 mL). The resulting solution was allowed to warm to room temperature before the addition of a solution of 1-Boc-3-azetidinone (0.58 g, 3.4 mmol) in THF (12 mL). The reaction mixture was stirred at room temperature for 2 hours and partitioned between brine and DCM. The organic layer was isolated, washed with brine, dried over MgSO4 and concentrated. The crude residue was then purified by flash chromatography (0-100% EtOAc in heptane) to give the title compound (1.15 g, 93%). LCMS m/z: 421.3 (MH+).

Provenance & Evidence