abstract |
Disclosed is a process for the synthesis of compounds of Formula I n nby sequentially aminating, first with a primary amine and then with a secondary amine, an intermediate compound of the structure of Formula E1,n n nwherein R 1 is a linear, branched, or cyclic alkyloxy functional group of the structure (—R 2a —OH), R 2a is a linear, branched or cyclic alkyl group, R 2 is a linear, branched or cyclic alkyl group, and R 3 is an alkylene-heterocycle, said process comprising forming intermediate compound of Formula E1 by reacting, in a refluxing reaction solvent selected from alcohols having 5 or less carbon atoms and mixtures of two or more thereof, a methanol solution of a salt of a 4-alkyl-3-amino-pyrazole compound of Formula C1,n n nwith a diamidization reagent selected from dimethylmalonate, monomethylmalonyl-chloride, and malonyl dichloride in the presence of a Lewis base having sufficient proton affinity to abstract a proton from the 1-position nitrogen on the pyrazole ring. |