Chloroacetaldehyde → Thiazole, 2-[(3,4,4-trifluoro-3-butenyl)thio]-

15.1 g (64.8 mmol; purity 86.3%) of 3,4,4-trifluoro-3-butenyl dithiocarbamate in 100 ml of dioxane are admixed with 0.2 ml of conc. hydrochloric acid and 12.4 g (71.2 mmol) of 45% aqueous chloroacetaldehyde solution. The mixture is boiled for 4 h under argon, and another 1 ml of chloroacetaldehyde solution is added after 2 h. The mixture is then concentrated by evaporation under reduced pressure, the residue taken up in dichloromethane and washed with water, and the organic phase concentrated by evaporation under reduced pressure after drying over MgSO4. 16 g (94.4% of theory; purity by GC/MS: 86.1 area %) of an oil are obtained, which may be distilled at 0.4 T/86° C.

1. concentrationThe mixture is then concentrated by evaporation under reduced pressure
2. washwashed with water
3. concentrationthe organic phase concentrated by evaporation under reduced pressure
4. dry with materialafter drying over MgSO4
5. custom16 g (94.4% of theory; purity by GC/MS: 86.1 area %) of an oil are obtained
6. distillationwhich may be distilled at 0.4 T/86° C.

ORD-Eintrag

ord-e494e05befe84184b27d75692c70f54b

Quelldatensatz

uspto-grants-2008_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07439408B2