p-Toluenesulfonic acid → HCID 54491445, compound

Participants

Reaction Steps

A solution of the product from Step A of Example 21 above (1320 mg, 4.56 mmol), pyrrolidine (972 mg, 13 mmol) and p-toluenesulfonic acid (33 mg) in benzene (30 mL) was refluxed through 3a molecular sieves for about 17 h. The reaction mixture was cooled to room temperature and concentrated in vacuo. The residue was dissolved in benzene (10 mL) and cooled to about 0° C. Methyl bromoacetate (1530 mg, 10 mmol) was added dropwise. The reaction mixture was slowly allowed to warm to room temperature and then was heated under reflux for about 17 h at which point H2O (5 mL) was added. After refluxing for about another 2 h, the reaction mixture was cooled to room temperature and extracted with EtOAc (3×100 mL). The combined organic extracts were dried and concentrated in vacuo. The crude residue was chromatographed on SiO2-gel using 15% ethyl acetatel hexanes to give 280 mg of product. 1H NMR (250 MHz, CDCl3): d 7.35 (m, 5H), 4.5 (m, 1H), 3.8 (s, 3H), 3.4 (dd, 1H), 3.1 (m, 1H), 2.85 (m, 4H), 2.6 (m, 1H), 2.4 (m, 1H), 1.5 (s, 9H); MS (APCI): 362 (M+1).

Provenance & Evidence