反応 #65588

反応方程式

2-cyclododecylethyl isocyanate

tetronic acid

triethylamine

KBr

→

4-Hydroxy-2-oxo-2.5-dihydro-furan-3-carboxylic acid-2-cyclododecyl-ethylamide

溶媒

chloroform

反応条件

後処理

1. 1
   その他The reaction mixture was quenched with 1N HCl
2. 2
   その他the layers separated
3. 3
   乾燥the organic fraction dried over MgSO4
4. 4
   ろ過filtered
5. 5
   その他chromatographed
6. 6
   その他to give a yellow solid

実験手順

To a dry flask containing 40 mL of chloroform was added 1.87 g (18.7 mmol) of tetronic acid, 2.29 g (18.7 mmol) of 4-N,N-dimethylaminopyridine, 2.6 mL (18.7 mmol) of triethylamine followed by 4.4 g (18.7 mmol) of 2-cyclododecylethyl isocyanate. The reaction mixture was allowed to stir overnight at room temperature, after which time a small amount of starting materials was still evident by TLC. The reaction mixture was quenched with 1N HCl, the layers separated, the organic fraction dried over MgSO4, filtered, and stripped of solvent. The residue was flash chromatographed using acidic silica gel eluting with 25% EtOAc/hexane to give a yellow solid. M.P. 135°-137° C. Spectral data follow: 1H NMR (DMSO-d6) δ 8.05 (bs, 1H), 4.6 (s, 2H), 4.2 (bs, 10H), 3.25 (t, 2H), 2.5 (s, 3H), 1.2-1.4 (bm, >20H); IR (KBr) 3340, 2920, 2850 (C--H), 1750, 1650 cm-1 (C=0);

出典