Reaktion #590937

Reaktionsgleichung

4-(2-isopropyl-6-phenyl[1,2,4]triazolo[1,5-a]pyrimidin-5-yl)benzaldehyde

tert-butyl 4-(hydrazinocarbonyl)piperidine-1-carboxylate

pyridine-2-carbonitrile

NaBH(OAc)3

NaBH(OAc)3

→

2-Isopropyl-6-phenyl-5-(4-{[4-(5-pyridin-2-yl-1H-1,2,4-triazol-3-yl)piperidin-1-yl]methyl}phenyl)[1,2,4]triazolo[1,5-a]pyrimidine

Lösungsmittel

DMF

methanol

acetic acid

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent is removed by evaporation after 20 h
2. 2
   Sonstigethe residue is purified by chromatography on silica gel (dichloromethane/[dichloromethane+7M NH3 in methanol])
3. 3
   Sonstigeto yield the product

Vorschrift

2.2 ml triethylamine is added to a solution of 1.90 g 2-(5-piperidin-4H[1,2,4]triazol-3-yl)-pyridine*2HCl (prepared from tert-butyl 4-(hydrazinocarbonyl)piperidine-1-carboxylate and pyridine-2-carbonitrile according to a procedure described in U.S. Pat. No. 4,011,218 or WO2005100344) in 140 ml methanol. To this solution a solution of 2.30 g 4-(2-isopropyl-6-phenyl[1,2,4]triazolo[1,5-a]pyrimidin-5-yl)benzaldehyde in 140 ml DMF is added, followed by 2.4 ml glacial acetic acid and 3.0 g NaBH(OAc)3. The resulting mixture is stirred at room temperature. Four additional portions of 2 equivalents NaBH(OAc)3 are added after 2, 4, 5 and 8 hours. The solvent is removed by evaporation after 20 h and the residue is purified by chromatography on silica gel (dichloromethane/[dichloromethane+7M NH3 in methanol]) to yield the product.

Quelle