engleski

Infrared and crystalogryphic study of complexation of N, N-dimethylformamide with racemic 1, 1'-bi-2-naphthol

1, 1'-bi-2-naphthol (BINOL) is very important chemical in farmaceutical industry. It exists in two atropoisomeric forms, namely (+)-(R)-BINOL, and (-)-(S)-BINOL. It is found that satisfactory efficient separators of these atropoisomers are Pirkle-type chiral stationary phases based on (S)-leucine-N-(3, 5-dinitrobenzene). However, the mechanism of separation is not yet clear. It is obvios that BINOL forms hydrogen bonds with one or more sites of chiral stationary phase, and separation occurs when these hydrogen bond(s) orientate one atropoisomer of BINOL to position adequate for formation of intermolecular bond (probably π - π interaction) with another site (probably 3, 5-benzoyl group). Because of many possible binding sites at chiral stationary phase, it is better to study interactions of BINOL molecule with small molecules, which act as model compounds of sites with which BINOL interacts. The first molecule studied in this regard is N, N-dimethylformamide (DMF), which is model of amide sites of chiral stationary phase. In this work, we present the part of our investigation of DMF interaction with BINOL. DMF forms stable complex with BINOL in solutions, and it is found that both molecules co-crystalise from dichloromethane solution, as evident from FTIR spectra. Crystal structure of formed complex is found, and thermal decomposition of this complex in solid state is studied by FTIR spectroscopy.

DIACETYLENIC DEHYDROBENZOANNULENE; IR spectroscopy

nije evidentirano