Diisopropylamine → HCID 23557501, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 0.32 mL (2.2 mmol) of diisopropylamine in 10 mL of THF at 0° C. was treated with 0.92 mL (2.3 mmol) of 2.5 M n-butyllithium in sol'n in hexanes. The resulting solution was stirred at 0° C. for 10 min, then cooled to −78° C. A solution of 0.51 g (1.8 mmol) of (1-tert-butoxycarbonylpiperidin-4-yl)acetic acid, ethyl ester (from Piperidine 35, Step A) in 2 mL of THF was added. After stirring for 30 minutes, a solution of 0.26 g (2.1 mmol) 5-chloropentanal in 2 mL of THF was added (J. Org. Chem. 1981, 46, 2007). The reaction was stirred for 1.75 hours at −78° C. and 3.5 hours at 0° C. After quenching the reaction with saturated NH4Cl, volatiles were removed under reduced pressure. The residue was partitioned between 100 mL of Et2O and 100 mL of H2O. After separating phases, the organic layer was washed with 100 mL of 0.5 N HCl and 100 mL of 1 N NaHCO3, dried over MgSO4 and concentrated. The residue was purified with a 40M Biotage column using 3:1 v/v of hexanes/EtOAc as the eluant to afford impure title compound: RF: 0.27 (7:3 v/v hexanes/EtOAc); 1H-NMR (500 MHz) δ 1.24–2.08 (m, 23H), 2.38 (t, J=6.2, 1H), 2.63–2.71 (m, 2H), 3.53–3.56 (m, 2H), 3.92 (m, 1H), 4.09–4.19 (m, 4H).

Provenance & Evidence