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 3 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 acetate/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