0000000000202526
AUTHOR
Hongqi Tao
Efficient synthesis of copillar[5]arenes and their host–guest properties with dibromoalkanes
An efficient method for the synthesis of copillar[5]arenes was developed with FeCl(3) as catalyst and different 1,4-dialkoxybenzenes and paraformaldehyde as reactants (yields: 50-85%). The host-guest property of (co)pillar[5]arenes and terminal dibromoalkanes was investigated by (1)H NMR measurements and an X-ray study. The complexation behavior of the copillar[5]arenes can be tuned by changing the substituents on the host. A complete complexation selectivity was found between pillar[5]- and pillar[6]arenes, which is an interesting aspect for sensor techniques.
Synthesis and Conformational Properties of Nonsymmetric Pillar[5]arenes and Their Acetonitrile Inclusion Compounds
The catalytic cyclocondensation of 1-butoxy-4-methoxy-2,5-bis(methoxymethyl)benzene (1d) affords a statistical mixture of the regioisomeric pillar[5]arenes 3a–d in high yield. The alkoxy groups are arranged stereoselectively in a mode so that they avoid steric interactions. The rotation of the benzene rings is, at room temperature, fast in terms of the NMR timescale and leads to a de facto Cs symmetry for 3a–c and a C5h symmetry for 3d. All four structural isomers can encapsulate two CH3CN guest molecules. The structure determinations are based on four crystal structure analyses (constitutions) and NMR spectroscopic measurements (conformations).
CCDC 821446: Experimental Crystal Structure Determination
Related Article: Luzhi Liu, Derong Cao, Yi Jin, Hongqi Tao, Yuhui Kou, H.Meier|2011|Org.Biomol.Chem.|9|7007|doi:10.1039/c1ob05871a
CCDC 777752: Experimental Crystal Structure Determination
Related Article: Yuhui Kou, Hongqi Tao, Derong Cao, Zhiyong Fu, D.Schollmeyer, H.Meier|2010|Eur.J.Org.Chem.|2010|6464|doi:10.1002/ejoc.201000718
CCDC 795257: Experimental Crystal Structure Determination
Related Article: Yuhui Kou, Hongqi Tao, Derong Cao, Zhiyong Fu, D.Schollmeyer, H.Meier|2010|Eur.J.Org.Chem.|2010|6464|doi:10.1002/ejoc.201000718
CCDC 777751: Experimental Crystal Structure Determination
Related Article: Yuhui Kou, Hongqi Tao, Derong Cao, Zhiyong Fu, D.Schollmeyer, H.Meier|2010|Eur.J.Org.Chem.|2010|6464|doi:10.1002/ejoc.201000718
CCDC 777753: Experimental Crystal Structure Determination
Related Article: Yuhui Kou, Hongqi Tao, Derong Cao, Zhiyong Fu, D.Schollmeyer, H.Meier|2010|Eur.J.Org.Chem.|2010|6464|doi:10.1002/ejoc.201000718