Brucine inclusion complex

Resolution of Alcohols. Although not a well exploited use of brucine, a variety of secondary benzylic alcohols have been resolved by complexation and crystallization with brucine (eq 5). About a dozen alcohols were obtained in close to enantiomeric purity by this procedure. Also resolved by crystallization of their brucine inclusion complexes were a series of tertiary propargylic alcohols (eq 6). In this case, the enantiomer that does not crystallize with brucine can be obtained in almost complete optical purity from the mother liquors. 

Resolution of Ketones. Brucine has not been used very extensively for the resolution of neutral compounds. However, in some cases, ketones or ketone derivatives may form diastereomeric inclusion complexes with brucine, providing an opportunity for their resolution. For example, the cyanohydrin of a bicyclic ketone has been resolved by this procedure (eq 10). Following resolution of the cyanohydrin, the ketone was regenerated and determined to be of 94% ee. 

Alcohol and cyanohydrin guests easily form inclusion complexes with brucine host... 

ABSTRACT. Novel optical resolutions of guest compounds by inclusion complex formation with optically active host compound are reviewed Tertiary acetylenic alcohols, cyanohydrins, and secondary alcohols were resolved by complexation with alkaloids such as brucine or sparteine. Cycloalkanones, 2,3 -epoxycyclohexanones, and some other neutral compounds were resolved by complex formation with optically active diacetylenic diol. Mutual optical resolution of bis-g-naphthol and sulfoxides by complex formation was also reviewed. 

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