Enantiomer separation of rac-2,2′-dihydroxy-1,1′-binaphthyl (BNO) by inclusion complexation with racemic or achiral ammonium salts and a novel transformation of a 1:1:1 racemic complex of BNO, Me4N+·Cl− and MeOH into a conglomerate complex in the solid st

The complete simultaneous and mutual enantiomer resolution of 2,2′-dihydroxy-1,1′-binaphthyl (BNO) and N-(3-chloro-2-hydroxypropyl)-N,N,N-trimethylammonium chloride, Me3N+CH2CH(OH)CH2Cl·Cl− into their enantiomers by inclusion complexation between their racemates in EtOH in the presence of a chiral seed crystal is reported. The enantiomer resolution of the rac-BNO was also accomplished easily by inclusion complexation with achiral ammonium salts, N-(2-hydroxyethyl)-N,N,N-trimethylammonium chloride, Me3N+CH2CH2OH·Cl− and tetramethylammonium chloride, Me4N+·Cl−. Inclusion complexation of the rac-BNO with Me3N+ CH2CH2OH·Cl− gave only a 1:1 conglomerate inclusion complex but not a racemic complex. Recrystallization of the rac-BNO and an equimolar amount of Me4N+·Cl− from MeOH (7 ml) and MeOH (15 ml) gave a 1:1:1 racemic complex, BNO·Me4N+·Cl−·MeOH and a 1:1 conglomerate complex, BNO·Me4N+·Cl−, respectively. Novel transformation of the former racemate into the latter conglomerate occurred by heating or by exposure to MeOH vapor in the solid state.