Substituent Effects in 3,3’ Bipyrazole Derivatives. X-ray Crystal Structures, Molecular Properties and DFT Analysis

The single crystal X-ray structure of new 1,1’-bis(2-nitrophenyl)-5,5’-diisopropyl-3,3’-bipyrazole, 1, is triclinic P I–, a = 7.7113(8), b 12.3926(14), c 12.9886(12) Å, α 92.008(8), β 102.251(8), γ 99.655(9)°. structural arrangement compared to that 5,5’-diisopropyl-3,3’-bipyrazole, 5, whose found tetragonal I41/a, 11.684(1), 19.158(1) Å. comparison also extended the structures previously determined for 1,1’-bis(2-nitrophenyl)-5,5’-propyl-3,3’-bipyrazole, 2, 1,1’-bis(4-nitrophenyl)-5,5’-diisopropyl-3,3’-bipyrazole, 3, and 1,1’-bis(benzyl)-5,5’-diisopropyl-3,3’-bipyrazole, 4. Density Functional Theory (DFT) calculations are used investigate molecular geometries determine global reactivity parameters. geometry isolated molecules arrangements in solid state analyzed according nature groups connected bipyrazole core.