Novel synthesis of 5-amino-3-bromo-1-(tert-butyl)-1H-pyrazole-4-carbonitrile: a versatile intermediate for the preparation of 5-amino-3-aryl-1-(tert-butyl)-1H-pyrazole-4-carboxamides.
A simple, novel, and efficient route for the synthesis of 5-amino-3-aryl-1-(tert-butyl)-1H-pyrazole-4-carboxamides 1 has been devised. Preparation of pyrazole bromide 3 from potassium tricyanomethanide can be accomplished in only two steps in good yield and features a selective Sandmeyer reaction on the corresponding diaminopyrazole. This allows for a more versatile synthesis of 5-amino-3-aryl-1-(tert-butyl)-1H-pyrazole-4-carboxamides 1 than was previously possible.
GlaxoSmithKline, Cancer Research, Protein Dynamics Discovery Performance Unit, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, USA.
Mark A
MA
Bobko
Arun C
AC
Kaura
Karen A
KA
Evans
Dai-Shi
DS
Su
D000577:Amides / Q000138:chemical synthesis* / Q000737:chemistry; D020650:Combinatorial Chemistry Techniques; D006842:Hydrocarbons, Brominated / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011720:Pyrazoles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D000577:Amides; D006842:Hydrocarbons, Brominated; D011720:Pyrazoles