Reaktion #71847

Reaktionsgleichung

WSC hydrochloride

tert-butyl 7-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate

tert-Butyl 7-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate

hydrochloric acid ethyl acetate

N,N-diisopropylethylamine

monoethyl succinate

→

title compound

Ausbeute 38.3%

Ethyl 4-(7-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-2,3-dihydro-4H-1,4-benzoxazin-4-yl)-4-oxobutanoate

Ausbeute 38.3%

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigePurification
2. 2
   Waschenby silica gel column chromatography (elution solvent: hexane/ethyl acetate=3/1, 2/1, 2/3, 0/1)

Vorschrift

The same operation as in Example (93a) was performed using tert-butyl 7-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate obtained in Example (95c) (0.11 g, 0.27 mmol), a 4 N hydrochloric acid/ethyl acetate solution (8 ml, 32 mmol), monoethyl succinate (150 mg, 1 mmol), WSC hydrochloride (288 mg, 1.5 mmol), N,N-diisopropylethylamine (0.52 g, 4 mmol) and DMAP (10 mg). Purification by silica gel column chromatography (elution solvent: hexane/ethyl acetate=3/1, 2/1, 2/3, 0/1) gave 45 mg of the title compound as a light yellow solid (38%).

Quelle