The effects of hexafluoroisopropanol on guest binding by water-soluble capsule and cavitand hosts.
Encapsulation of amphiphilic guests in a water-soluble cavitand is enhanced by the addition of hexafluoroisopropanol (HFIP). While binding of n-alkanes in cavitands in HFIP/D2O mixtures was similar to that observed in 100% D2O, the binding of guests with terminal polar groups was quite different. Several α,ω-bolaamphiphiles: alkyldiols (C10-C12), a dinitrile (C14) and a diacid (C16) became encapsulated in HFIP/D2O solutions. As little as 15% HFIP v/v in D2O moves the guest from cavitand to the dimeric capsule. The unusual binding of polar functional groups inside the confined space is deduced from NMR COSY spectra and supported by DFT calculations. Alkane guests are also encapsulated in 100% HFIP.
Skaggs Institute for Chemical Biology, The Scripps Research Institute, and Department of Chemistry, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. jrebek@scripps.edu.
Jesse V
JV
Gavette
Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens 116 35, Greece.
Ioannis D
ID
Petsalakis
Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens 116 35, Greece.
Giannoula
G
Theodorakopoulos
Skaggs Institute for Chemical Biology, The Scripps Research Institute, and Department of Chemistry, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. jrebek@scripps.edu.
Kang-Da
KD
Zhang
Skaggs Institute for Chemical Biology, The Scripps Research Institute, and Department of Chemistry, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. jrebek@scripps.edu.
Yang
Y
Yu
Department of Chemistry, Fudan University, 220 Handan Road, Shanghai, 200433, China and Skaggs Institute for Chemical Biology, The Scripps Research Institute, and Department of Chemistry, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. jrebek@scripps.edu.
Julius
J
Rebek