Nitrite → Propyl-(4,5,6,7-tetrahydro-benzothiazol-6-yl)-amine
Reaction equation
Br.Br.[CH2:3]([NH:6][CH:7]1[CH2:16][CH2:15][C:10]2[N:11]=[C:12](N)[S:13][C:9]=2[CH2:8]1)[CH2:4][CH3:5].N([O-])=O.P(P(O)(O)=O)(O)(O)=O.[OH-].[Na+]>Cl>[CH2:3]([NH:6][CH:7]1[CH2:16][CH2:15][C:10]2[N:11]=[CH:12][S:13][C:9]=2[CH2:8]1)[CH2:4][CH3:5]Participants
Conditions
- Temperature
- -30 °C
Procedure
To a solution of 14.5 g (38.9 mmol) N6-propyl-4,5,6,7-tetrahydro-benzothiazole-2,6-diamine dihydrobromide in 220 mL concentrated aqueous hydrochloric acid at −30° C. is drop wise added 66.3 mL of an aqueous 1N solution nitrite over the course of 30 minutes. After further stirring for 1 hour at the same temperature 5.44 ml (52.5 mmol) of a 50% aqueous solution hypophosphoric acid is added. The reaction mixture is stored at 4° C. overnight. After having cooled down the solution again to −30° C. the mixture is slowly basified with 40% aqueous sodium hydroxide solution while temperature is kept at −30° C. The resulting mixture is warmed up to room temperature and extracted with Chloroform/Ethanol 5:1 (3×250 mL) The solution is dried over anhydrous sodium sulfate and concentrated in vacuum. The brown oil obtained is chromatographed over silica gel, eluting with dichloromethane/methanol 97:3 under ammonia atmosphere.
Workup
- customat −30° C.
- customover the course of 30 minutes
- additionis added
- customis kept at −30° C
- temperatureThe resulting mixture is warmed up to room temperature
- extractionextracted with Chloroform/Ethanol 5:1 (3×250 mL) The solution
- dry with materialis dried over anhydrous sodium sulfate
- concentrationconcentrated in vacuum
- customThe brown oil obtained
- customis chromatographed over silica gel
- washeluting with dichloromethane/methanol 97:3 under ammonia atmosphere
Sources & evidence
- ORD record
- ord-a5d414f148fb479688f7c99dfe283d04
- Source dataset
- uspto-grants-2013_03
- Patent number
- US08389555B2
Reaction notes
Loading…