Optically active 1,2-diaminocyclohexane and its derivatives have been widely used as chiral ligands of catalyst for asymmetric reactions, as effective host compounds for the isolation or optical resolution of organic guest molecules through the formation of crystalline inclusion complexes, as chiral stationary phases for chromatographic separation, and as chelating agents for many minerals and metals. 1-5 The wideranging and important applications of these compounds in organic synthesis have

more »

... mulated great interest in developing efficient methods for their preparation. Recently, during the course of a one-pot synthesis of derivative 1 of the 1,2diaminocyclohexane, it was found that the reaction of (1R,2R)-1,2-diaminocyclohexane with 2-naphthol and benzaldehyde under solvent-free condition did not afford the desired product; accidentally, a novel compound was obtained. In order to obtain a clear understanding of the structural feature of this novel compound (2), we also obtained its single crystals suitable for an X-ray crystallographic study by recrystallization from a methanol solution. In this paper, we wish to report on the synthesis and crystal structure of 2. x29 ANALYTICAL SCIENCES 2005, VOL. 21 X-ray Structure Analysis Online The reaction of (1R,2R)-1,2-diaminocyclohexane with 2-naphthol and benzaldehyde gave the title compound, 1-{[2-(1,3diphenyl-1H-naphtho[1,2-e][1,3]oxazin-2-yl)cyclohexylamino]phenylme thyl}naphthalen-2-ol (2), under solvent-free condition. The results of an X-ray single crystal analysis indicate that there are five chiral centers and two different types of intramolecular hydrogen bonds in the title compound. One is a O-H·N hydrogen bond, and the other is a N-H·N hydrogen bond.