4-Methoxy cinnamic acid → (S)-Benzyl N-(4-Methoxycinnamoyl)pipecolate

Beteiligte Stoffe

Reaktionsschritte

To a solution of 145 mg (0.37 mmol) of (S)-Benzyl pipecolate salt (134) (described in Example 1) in 8.0 mL of methylene chloride was added 102 mg (0.57 mmol) of 4-methoxycinnamic acid, 107 mg (0.55 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and 130 μL (0.74 mmol) of diisopropylethylainine, The resulting solution was stirred at ambient temperature for 12 h and was then concentrated under reduced pressure. Flash chromatography (elution with 1:1 ethyl acetate-hexane) gave 91 mg (65%) of the amide (112) as a colorless oil. 1H NMR (300 MHz, CDCl3) δ7.66 (d), 7.50 (d), 7.35 (m), 6.90 (d), 6.82 (d), 6.63 (d), 5.55 (d), 5.20 (br s), 4.86 (br s), 4.67 (br d) 4.03 (br d), 3.83 (s), 3.37 (dt), 2.78 (dt) 2.33 (br d), 1.74 (m), 1.43 (m). Rf 0.40 (1:1 ether-hexane).

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