Réaction #1994305

Équation de réaction

(2Z,5E)-2-amino-6-(4-chlorophenyl)-4-oxo-hexa-2,5-dienoic acid ethyl ester

(2Z,5E)-2-Amino-6-(4-chlorophenyl)-4-oxo-hexa-2,5-dienoic acid ethyl ester

→

6-(4-Chlorophenyl)-4-oxo-1,4,5,6-tetrahydropyridine-2-carboxylic acid ethyl ester

Solvants

1,4-dioxane

Conditions de réaction

Traitement

1. 1
   Autregave
2. 2
   Autrepurification by silica gel chromatography
3. 3
   Lavageeluting with 40% EtOAc/hexanes, 6-(4-chlorophenyl)-4-oxo-1,4,5,6-tetrahydropyridine-2-carboxylic acid ethyl ester (12; 25 g, 49%, 99% pure by HPLC) as an off-white solid

Mode opératoire

Using the procedure of Example 5, (2Z,5E)-2-amino-6-(4-chlorophenyl)-4-oxo-hexa-2,5-dienoic acid ethyl ester (8; 47 g, 0.168 mol) in 1,4-dioxane (470 mL) in a 2 liter Parr reactor gave, following purification by silica gel chromatography eluting with 40% EtOAc/hexanes, 6-(4-chlorophenyl)-4-oxo-1,4,5,6-tetrahydropyridine-2-carboxylic acid ethyl ester (12; 25 g, 49%, 99% pure by HPLC) as an off-white solid: mp 93-94° C.; 1H NMR (400 MHz, CDCl3) δ 7.36 (q, J=8.6 Hz, 4H), 5.82 (s, 1H), 5.72 (br s, 1H), 4.74 (dd, J=14.2, 5.0 Hz, 1H), 4.35 (q, J=7.1 Hz, 2H), 2.68 (dd, J=16.3, 14.2 Hz, 1H), 2.58 (dd, J=16.4, 5.0 Hz, 1H), 1.36 (t, J=7.1 Hz, 3H); HRMS-ESI (m/z): calcd for C14H14ClNO3, 279.067. found, 279.066.

Source