Reaktion #718407

Reaktionsgleichung

ethyl 7-amino-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylate

formamidine hydrochloride

→

7,8-dihydro-[1,4]dioxino[2,3-g]quinazolin-4(3H)-one

Ausbeute 84.0%

Lösungsmittel

formamide

Reaktionsbedingungen

Vorschrift

According to the procedure described in Example 6A Step 4, a mixture of ethyl 7-amino-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylate (1.45 g, 6.5 mmol) and formamidine hydrochloride (1.208 g, 15 mmol) in formamide (20 mL) was heated at 130° C. for 8 hours, to afford 7,8-dihydro-[1,4]dioxino[2,3-g]quinazolin-4(3H)-one as a solid (1.114 g, 84%). 1H NMR (300 MHz, CDCl3 and drops DMSO-d6) δ 11.80 (br, 1H), 7.88 (s, 1H), 7.63 (s, 1H), 7.13 (s, 1H), 4.36 (m, 4H); LC-MS (ESI) m/z 205 (M+H)+.

Quelle