title: Ammonia-driven chirality inversion and enhancement in enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylate mediated by diguanidino-γ-cyclodextrin.
abstract: In the supramolecular photocyclodimerization of 2-anthracenecarboxylate mediated by 6(A),6(D)-diguanidino-γ-cyclodextrin (CD), the chiral sense and enantiomeric excess of the photoproduct were dynamic functions of temperature and cosolvent to afford the (M)-anti head-to-head cyclodimer in 64% ee in aqueous methanol at -70 °C but the antipodal (P)-isomer in 86% ee in aqueous ammonia at -85 °C, while the corresponding diamino-γ-CD host did not show such unusual photochirogenic behaviors. The ee landscape was very steep against the temperature and sign-inverted against the ammonia content to reveal the opposite temperature dependence at low and high ammonia contents, for which an altered solvent structure and/or guanidinium-carboxylate interaction mode would be responsible.
authors.affiliation: Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry and State Key Laboratory of Biotherapy, West China Medical School, Sichuan University , 29 Wangjiang Road, Chengdu 610064, China.
authors.forename: Jiabin
authors.initials: J
authors.lastname: Yao
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yan
authors.forename: Jiecheng
authors.initials: J
authors.lastname: Ji
authors.forename: Wanhua
authors.initials: W
authors.lastname: Wu
authors.forename: Cheng
authors.initials: C
authors.lastname: Yang
authors.forename: Masaki
authors.initials: M
authors.lastname: Nishijima
authors.forename: Gaku
authors.initials: G
authors.lastname: Fukuhara
authors.forename: Tadashi
authors.initials: T
authors.lastname: Mori
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Inoue
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D000873:Anthracenes / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D003500:Cyclization; D019281:Dimerization; D019791:Guanidine / Q000031:analogs & derivatives*; D008027:Light; D008958:Models, Molecular; D055668:Photochemical Processes; D013237:Stereoisomerism; D047408:gamma-Cyclodextrins / Q000737:chemistry*
chemical_list: C476641:2-anthracenecarboxylate; D000873:Anthracenes; D002264:Carboxylic Acids; D047408:gamma-Cyclodextrins; D000641:Ammonia; D019791:Guanidine; C023792:gamma-cyclodextrin