A novel tubular hydrogen-bond pattern in a new diazaphosphole oxide: a combination of X-ray crystallography and theoretical study of hydrogen bonds

摘要

In the structure of 2-(4-chloroanilino)-1,3,2 lambda(4)-diazaphosphol-2-one, C12H11Cl-N3OP, each molecule is connected with four neighbouring molecules through (N-H)(2)center dot center dot center dot O hydrogen bonds. These hydrogen bonds form a tubular arrangement along the [001] direction built from R-3(3)(12) and R-4(3) (14) hydrogen-bond ring motifs, combined with a C(4) chain motif. The hole constructed in the tubular architecture includes a 12-atom arrangement (three P, three N, three O and three H atoms) belonging to three adjacent molecules hydrogen bonded to each other. One of the N-H groups of the diazaphosphole ring, not cooperating in classical hydrogen bonding, takes part in an N-H center dot center dot center dot pi interaction. This interaction occurs within the tubular array and does not change the dimension of the hydrogen-bond pattern. The energies of the N-H center dot center dot center dot center dot O and N-H center dot center dot center dot pi hydrogen bonds were studied by NBO (natural bond orbital) analysis, using the experimental hydrogen-bonded cluster of molecules as the input file for the chemical calculations. In the H-1 NMR experiment, the nitrogen-bound proton of the diazaphosphole ring has a high value of 17.2 Hz for the (2)J(H-P) coupling constant.