Relationship between Isomerization of Host Frameworks and Packing Coefficients of Host Cavities in Organic Porous Crystals

Masashi Shigesato^a, Nungruethai Yoswathananont^a, Kazuki Sada^a, Mikiji Miyata^a, Kazunori Nakano^b, Kohji Tashiro^c

^aMaterial and Life Science Graduate School of Engineering, Osaka University, Yamadaoka2-1, Suita, Osaka 565-0871,Japan, ^bNagoya Municipal Industrial Research Institute, 6-3-4-41 Atsuta, Nagoya, Aichi 456-0058, Japan, ^cGraduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan

　 Polymolecular hosts are built with noncovalent bonds, and it is difficult to design and construct host frameworks on purpose.   Because the frameworks change variously according to molecular structures of host and guest molecules.   Now we on molecular recognition of steroidal bile acids systematically and quantitatively by introducing a parameter, called packing coefficients of host cavities (PC_Cavity).   PC_Cavity is volume ratios of host cavities to guest molecules.   We found the correlation between tha framework isomerizations and PC_Cavity in a series of inclusion compounds of cholic acid with monosubstituted benzenes.   We already reported that the PC_Cavity are in the small range of 55 ~ 70%.   Here, we report correlations between host framework isomerizations and PC_Cavity in various inclusion crystals of organic porous compounds with various guests.   Organic porous compounds change the host frameworks and/or the host-guest ratios to fit the shape and volume of guest molecules.    It is assumed that PC_Cavity of all the organic porous compounds are in small range.   Stability of organic porous inclusion crystals depends on the PC_Cavity.   However hosts with hydrogen-bonds between hosts and guests have relative larger range of PC_Cavity than hosts without hydrogen-bonds between hosts and guests.   The reason is that hydrogen-bonds between hosts and guests expand the PC_Cavity.

　 Symposium topic: A5

Name of the presenting author: SHIGESATO Masashi

Address               Material and Life Science, Graduate School of Engineering, Osaka University, Yamadaoka2-1, Suita, Osaka 565-0871,Japan
Email                   shigesa@ap.chem.eng.osaka-u.ac.jp
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