Reaktion #975257
ord-3a868bdd58264999845fa3179f789be8
Reaktionsgleichung
Reagenzien
Reaktionsbedingungen
Vorschrift
Indazolyl ethers can be prepared by the process outlined in Scheme 29. 6-Nitro-1H-2-hydroindazol-3-one 126 is protected such as with Boc2O and DMAP in CH2Cl2 at a temperature of about RT, to give the protected 6-nitro-2-hydroindazol-3-one. The protected 6-nitro-2-hydroindazol-3-one is reacted with an alcohol (where Rx is an appropriate substitutent selected from the possible substitutents on R) and Ph3P in a solvent, such as THF, and DEAD, at a temperature of about RT, to give the protected 6-nitro(indazol-3-yl)ether. The nitro intermediate is hydrogenated, such as with an H2 atmosphere in the presence of a catalyst, such as Pd/C, to give the protected 6-amino (indazol-3-yl)ether 127. The amine 127 is coupled and 2-chloronicotinic acid in a solvent, such as an alcohol, preferably pentanol, at a temperature above RT, preferably at a temperature above about 75° C., and more preferably at a temperature at about 130° C. to give the coupled and deprotected compound 128.