Acta Crystallographica Section E (Apr 2011)
[5-Hydroxy-3-phenyl-1-(pyridin-2-yl)pyrazol-5-olato]diphenylboron
Abstract
In the title compound, C26H20BN3O, the B atom has tetrahedral geometry and is linked to two phenyl rings, the O atom of the hydroxypyrazole ring and the N atom of the pyridinyl ring. A six-membered BOCNCN ring forms by coordination of the B atom and the pyridinyl N atom. The BOCNCN ring has an envelope conformation [dihedral angle = 36.7 (1)° between the planar ring atoms and the flap] with the B atom out of the plane. In the 1-(2-pyridinyl)-3-phenyl-5-hydroxypyrazole group, the pyridinyl ring, the phenyl ring and the pyrazole ring are almost coplanar: the pyrazole ring makes a dihedral angle of 9.56 (8)° with the pyridinyl ring and 17.68 (7)° with the phenyl ring. The crystal structure is stabilized by π–π stacking interactions involving the pyridinyl and pyrazole rings of centrosymmetrically related molecules, with ring centroid separations of 3.54 (5) Å.