Synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives using dendritic polymer with amine-loaded catalytic capsules: computational approaches

Inositol cored primary amine-functionalized G0 dendritic polymer (INO-G0) was effectively synthesized and characterized by different spectroscopic and analytical techniques. 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives were synthesized using INO-G0 as the catalyst. They were prepared within 15 min in ethanol medium using the ultrasonic irradiation method and 95% yield was obtained. The synthesized 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives were characterized by recording Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectra. A novel computation approach was adopted, and the geometry of the 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives were optimized using Gaussian 09 software. The theoretical and optical band gaps were calculated. The absorption and emission properties were studied. The 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives exhibited absorption maxima in the range 430-460 nm and emission occurred in the range 400-700 nm range. The present method is green, efficient, and cost-effective. The catalyst could be reused up to four reaction cycles without significant loss of its activity. [GRAPHICS] .