Bromine → N-[5-(bromoacetyl)-4-methyl-1,3-thiazol-2-yl]acetamide, hydrobromide salt

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of Br2 (3.35 ml, 65.6 mmol) in 75 ml dioxane is added dropwise to a solution of N-(5-acetyl-4-methyl-1,3-thiazol-2-yl)acetamide (P6), obtained in Step I as described above, (10.40 g, 52.5 mmol) in 200 ml dioxane. The resulting mixture is heated at 50° C. for 19 hours. The solution turns from dark red to beige and remains a heterogeneous mixture. By analytical HPLC, only 2.8% of starting material is detected. The suspension is filtered, washed with a 1:2 EtOAc/hexanes mixture (50 ml) and air dried for 15 min, to give Intermediate 1 as a beige solid (11.2 g, 60%). It is used in bis-thiazol synthesis as HBr salt or as parent, after 5 min treatment with Amberlyst A21 in DCM/MeOH mixture.

Herkunft & Nachweise