title: Recognition of Multiple Methyl Groups on Aromatic Rings by a Polyaromatic Cavity.
abstract: The methyl group is a small substituent, usually showing relatively weak or no interactions with other functional groups and metal ions. Herein, we present the recognition of the number of methyl groups on synthetic and natural aromatic compounds (i.e., benzene and xanthine derivatives, respectively) by the 1 nm-sized polyaromatic cavity of a coordination capsule in water. Detailed competitive encapsulation experiments as well as X-ray crystallographic analysis revealed that multiple guest-host CH3 -polyaromatic interactions in the confined nanospace are key driving forces for the high selectivity.
authors.affiliation: Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamashina
authors.affiliation: Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Matsuno
authors.affiliation: Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Sei
authors.affiliation: Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Munetaka
authors.initials: M
authors.lastname: Akita
authors.affiliation: Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan. yoshizawa.m.ac@m.titech.ac.jp.
authors.forename: Michito
authors.initials: M
authors.lastname: Yoshizawa
keywords: caffeine; capsule; methyl group; molecular recognition; polyaromatic ring