反应详情

A solution of 100 mg (0.56 mmol) 6-fluoro-3-methyl-1H-indazole-5-carbaldehyde (Example 3A) and 146 mg (1.24 mmol) 3-amino-4,4-difluorobut-2-enenitrile [obtainable by Thorpe reaction of acetonitrile with 2,2-difluoroacetonitrile, cf. Org. React. 15, 1 (1967), ibid. 31, 1 (1984)] in acetic acid (0.54 ml) containing powdered 4 Å molecular sieve was heated to reflux temperature for 5 h. After cooling, the reaction mixture was diluted with THF and filtered. The filtrate was directly purified by preparative RP-HPLC (acetonitrile/water+0.1% TFA gradient) yielding 136 mg (64% of th.) of the title compound.

1. temperaturewas heated
2. temperatureto reflux temperature for 5 h
3. temperatureAfter cooling
4. filtrationfiltered
5. customThe filtrate was directly purified by preparative RP-HPLC (acetonitrile/water+0.1% TFA gradient)