2-AMINO-5-FORMYLTHIAZOLE HCL synthesis

Yield:-

Reaction Conditions:

Stage #1: tert-butyl (5-formylthiazol-2-yl)carbamatewith trifluoroacetic acid in dichloromethane at 20;Cooling with ice;
Stage #2: with hydrogenchloride in 1,4-dioxane;chloroform;Cooling with ice;

Steps:

1.2

(2) To a solution of the above compound (1-b) (64.5 g, 282 mmol) in methylene chloride (322 ml) was added dropwise trifluoroacetic acid (322 ml) under ice-cooling over 20 minutes. The reaction mixture was stirred at room temperature for 2 hours, and evaporated. To the residue was added chloroform (50 ml), and then thereto was added dropwise a solution of 4N hydrogen chloride in dioxane (300 ml) under ice-cooling. The mixture was evaporated, and then the residue was washed with ethyl acetate and dried to give the above compound (1-c) (41.3 g) as a monohydrochloride. MS(m/z)APCI: Not Determined.

References:

EP2105435,2009,A1 Location in patent:Page/Page column 54