A REINVESTIGATION OF THE QUINOIDAL EFFECT IN N-N-PROPYL-2-OXO-1-NAPHTHYLIDENEMETHYLAMINE

In the title compound C14H15NO (systematic name: 1-n-propylaminomethyl ene-2-naphthalenone), an intramolecular N-H ... O hydrogen bond [N ... O 2.578(2), N-H 0.775, H ... O 1.936 Angstrom] arises when the hydrox yl-H atom of the Schiff base prepared from 2-hydroxy-1-naphthaldehyde and n-propylamine shifts to the N atom. This is the consequence of the pronounced quinoidal effect in the 2-oxo-1-naphthaldimine moiety whic h has a very short C3=C4 bond of 1.343 (3) Angstrom. The spatial orien tation of the N-substituent with respect to the rest of the molecule ( which is planar) depends on the surroundings of the molecules defined by the crystal packing.