1,1,3,3-Tetramethylguanidine → (Z)-2-[[2-chloro-4-[3-(3-hydroxyphenyl)-1-oxopropan-1-yl]benzoyl]amino]-3-(quinolin-3-yl)propenoic acid methyl ester

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Reaction Steps

1,1,3,3-Tetramethylguanidine (94 μL, 0.75 mmol) was added to a solution of rac.-N-[2-chloro-4-[3-(3-hydroxyphenyl)-1-oxopropan-1-yl]benzoyl]-2-(dimethoxyphosphinyl)glycine methyl ester (Example 133; 244 mg, 0.5 mmol) in tetrahydrofuran (7 mL) at −20° C. After 30 min, quinoline-3-carboxaldehyde (82.5 mg, 0.525 mmol) was added and the solution was stirred at room temperature for 16 h. The solvent was evaporated and ethyl acetate (30 mL) was added. The solution was washed with saturated sodium bicarbonate solution (15 mL) and the aqueous layer was extracted with ethyl acetate (10 mL). Each organic layer was washed with brine. The combined organic layers were dried (MgSO4), filtered, evaporated and chromatographed over silica gel (20-50% ethyl acetate/hexanes) to (Z)-2-[[2-chloro-4-[3-(3-hydroxyphenyl)-1-oxopropan-1-yl]benzoyl]amino]-3-(quinolin-3-yl)propenoic acid methyl ester (221 mg, 86% yield) as an orange-yellow solid.

Provenance & Evidence