Abstract

X-ray Crystallographic Studies On Systemic Fungicide �������²-4(-Chlorophenoxy)- �������±-(1,1-Dimethylethyl) 1H-1,2,4-Triazole-1-Ethanol

Author(s): Jyotsna Sengar

In recent part it has been observed that some of these fungicides are loosing their effects and becoming resistant to them. Analogous compounds can be designed as substitute, if their structures are known. A rational approach to test these fungicides is to know the three dimensional structure of these compounds and macromolecular receptor sites as well as their molecular complex The structures of these compounds can be obtained by X-ray diffraction method in crystalline form and they will invariably be similar to their structure in solutions. Crystal and molecular structure of β-4(-chlorophenoxy)-α(1,1 dimethylethyl)1H-1,2,4-triazole-1-ethanol The composition of these crystals are confirmed by comparing the infra-red spectra Of the two components. The unit cell parameters a = 8.130(2) Å b = 16.790(2)Å c=21. 990Å. The space group is determined to be P21/n. The measured density is 1.3215g/cm3 and calculated density is 1. 3102g/cm3. The average bond distances of C-H and N-H types are 0. 96(2)Å and 0. 90(1)Å respectively. The bond lengths and angles in the benzene rings show regular features in both the molecules. The C(4)-Cl(1) and Cl(2)-C(18) distances are 1.748(1)Å and 1.747(2)Å comparable to other structures although similar structures are not available for comparison. These distances are short and shortening may be due to delocalization of electrons from the benzene rings. The whole molecules appeared to be twisted and folded and reason may be due to stacking constraints. The bond distances around C(7)and C(21) are as usual shorter than single bond values. They may also appear to bear a partial double bond character. The C(7)-O(1) and C(21)- O(3) distances are 1.4028(1)Å and1.4114(2)Å respectively. These distances do not change significantly in similar structures,despite variable intermolecular interactions through them. The bond distances in the five member rings are comparable to corresponding distances inheterocyclic rings1. 339(Å).