title: Effects of solvent on inclusion complexation of a chiral dipeptide toward racemic BINOL.
abstract: The effects of reaction solvent on inclusion complexation of a chiral dipeptide (3S,6S)-1 derived from (S)-proline toward racemic BINOL was investigated, discovering that the reaction solvent played a crucial role in determining the inclusion complexation behavior of dipeptide (3S,6S)-1 toward rac-BINOL. (3S,6S)-1 did not show any chiroselective or achiroselective complexation toward rac-BINOL in polar protic solvents such as methanol and ethanol, polar aprotic solvents including trichloromethane and THF, while in polar aprotic solvent ethyl acetate and apolar aprotic solvents benzene, (3S,6S)-1 displayed achiroselective complexation toward rac-BINOL. However, the resulting heterocomplex HC-2 from benzene and HC-3 from ethyl acetate have a different composition. Single crystal X-ray diffraction analysis demonstrates that the two heterocomplexes are formed via different H-bond interaction patterns, in which the reaction solvent has a dramatic effect. Furthermore, this work provides a relatively green method for quantitative enantiomeric enrichment of nonracemic BINOL, in which unacceptable and toxic benzene was replaced by ethyl acetate.
authors.affiliation: College of Chemistry and Materials, South-Central University for Nationalities, Wuhan, Republic of China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Hu
authors.affiliation: College of Chemistry and Materials, South-Central University for Nationalities, Wuhan, Republic of China.
authors.forename: Yuyuan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Chemistry and Materials, South-Central University for Nationalities, Wuhan, Republic of China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Shi
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Republic of China.
authors.forename: Zixing
authors.initials: Z
authors.lastname: Shan
mesh_terms: D018360:Crystallography, X-Ray; D004151:Dipeptides / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D006860:Hydrogen Bonding; D000432:Methanol / Q000737:chemistry; D009284:Naphthols / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D004151:Dipeptides; D009284:Naphthols; D012997:Solvents; D000431:Ethanol; C412332:1,1'-bi-2-naphthol; D000432:Methanol
keywords: achiroselectivity; chiral dipeptide; heterocomplexation; inclusion complexation; racemic BINOL