A novel substrate directed multicomponent reaction for the syntheses of tetrahydro-spiro[pyrazolo[4,3- f ]quinoline]-8,5'-pyrimidines and tetrahydro-pyrazolo[4,3- f ]pyrimido[4,5- b ]quinolines via selective multiple C-C bond formation under metal-free conditions.

A versatile and substrate oriented multicomponent reaction for the syntheses of novel highly diastereoselective tetrahydro-1' H -spiro[pyrazolo[4,3- f ]quinoline-8,5'-pyrimidine]-2',4',6'(3' H )-triones (d.r. up to 20 : 1 ( syn  :  anti )) and tetrahydro-8 H -pyrazolo[4,3- f ]pyrimido[4,5- b ]quinoline-8,10(9 H )-diones via formation of selective multiple C-C bonds under identical reaction conditions ( viz. ethanol as a reaction medium and deep eutectic mixture as a catalyst) is demonstrated. Both approaches involve mild reaction conditions, use of non-hazardous solvents, and facilitate good to excellent reaction yields of the target compounds.