反应详情

Ester 152 (778 mg, 1.18 mmol) was treated with a 5% v/v solution of piperidine in DMF (6 mL). After stirring for 50 min, the reaction mixture was diluted with saturated NaHCO3 solution and washed once with Et2O. The aqueous layer was acidified to pH 2 with conc. HCl solution and extracted with a 4:1 mixture of CHCl3/i-PrOH (3×). The organic layers were combined, dried over MgSO4, filtered and concentrated to dryness, yielding acid 153 as yellowish oil (520 mg, 92%) which was used without purification. 1H NMR (400 MHz, CDCl3) δ 1.84 (quint, J=6.4 Hz, 2H), 2.35 (t, J=6.6 Hz, 2H), 3.26-3.29 (m, 2H), 4.52-4.67 (m, 8H), 5.04 (dt, J=22.2, 10.1 Hz, 1H), 5.20-5.27 (m, 4H), 5.30-5.40 (m, 4H), 5.751 (bs, 1H), 5.84-5.98 (m, 4H), 6.90 (d, J=10.3 Hz, 1H).

1. washwashed once with Et2O
2. extractionextracted with a 4:1 mixture of CHCl3/i-PrOH (3×)
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated to dryness