Crystal structure of (E)-2-[(2-bromopyridin-3-yl)-methylidene]-6-methoxy-3,4-dihydronaphthalen-1(2H)-one and 3-[(E)-(6-methoxy-1-oxo-1,2,3,4-tetrahydronaphthalen-2-ylidene)methyl]pyridin-2(1H)-one

Abstract

The title compounds C17H14BrNO2, (I), and C17H15NO3, (II), were obtained from the reaction of 6-methoxy-3,4-dihydro-2H-naphthalen-1-one and 2- bromonicotinaldehyde in ethanol. Compound (I) was the expected product and compound (II) was the oxidation product from air exposure. In the crystal structure of compound (I), there are no short contacts or hydrogen bonds. The structure does display π-π interactions between adjacent benzene rings and adjacent pyridyl rings. Compound (II) contains two independent molecules, A and B, in the asymmetric unit; both are non-planar, the dihedral angles between the methoxybenzene and 1H-pyridin-2-one mean planes being 35.07 (9)° in A and 35.28 (9)°in B. In each molecule, the 1H-pyridin-2-one unit participates in intermolecular N-H⋯O hydrogen bonding to another molecule of the same type (A to A or B to B). The structure also displays π-π interactions between the pyridyl and the benzene rings of non-equivalent molecules (viz., A to B and B to A).