Ethyl Acetate → HCID 69221321, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred solution n-butyllithium (165 mg, 2.6 mmol) in THF (5 mL) at −78° C. was added 12a (P=Boc, P2=Me, m=1) (570 mg, 2.3 mmol) in THF (5 mL). The reaction mixture was stirred at −78° C. for 2 h and then at −40° C. for an additional 1 h. EtOAc (20 mL) was added, followed by NH4Cl (5 mL, 10%) and water (10 mL). Organic layer was separated, dried over sodium sulfate and evaporated to dryness. The residue obtained was purified by silica gel column chromatography using 50% EtOAc in hexanes as eluant to provide 4-hydroxy-4-butylproline methyl ester 12b (P=Boc, m=1, R9=n-butyl) as a colorless oil (0.52 g, 73%): 1H NMR (300 MHz, CDCl3) δ 4.33 (m, 1), 3.76 (d, J=4.8, 3), 3.62 (m, 2), 3.28 (m, 1), 2.13 (m, 1), 2.02 (m, 1), 1.57 (m, 2), 1.29 (m, 12), 0.88 (m, 3); MS (ESPOS): 324 [M+Na]+.

Provenance & Evidence