Urea → 5,6,7,8-Tetrahydro-4H-oxazolo[4,5-d]azepin-2-ylamine

Reaction equation

[NH2:1][C:2]([NH2:4])=[O:3].Br.Br[CH:7]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9][C:8]1=O.[OH-].[Na+]>>[O:3]1[C:7]2[CH2:13][CH2:12][NH:11][CH2:10][CH2:9][C:8]=2[N:1]=[C:2]1[NH2:4]

Participants

Reactant 3

HCID 1176Urea

HCID 14798Sodium Hydroxide

HCID 226207665-Bromoazepan-4-one hydrobromide

Product 1

HCID 846497605,6,7,8-Tetrahydro-4H-oxazolo[4,5-d]azepin-2-ylamineYield 23.8%

Conditions

Temperature: 70 °C

Procedure

6.6 g urea was added to 6 g 5-bromo-azepan-4-one hydrobromide. The mixture was stirred 24 h at 70° C. The reaction was basified with 4 N NaOH and extracted with chloroform and ethylacetate. The combined organic layers were evaporated to yield 800 mg of the desired product.