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).

Eine leichte und effiziente Herstellung von Pillararenen und einem Pillarchinon

Crystal Structure and Host-Guest Binding Ability of Three Types of Pillar[5]arenes

A systematic research of the structural characterization and the host-guest binding abilities between three types of pillar[5]arenes 3–5 (3 for Structure Type I, 4 for Structure Type II and 5 for Structure Type III) is carried out by 1H NMR measurements and X-ray study. The results show that the configurations or symmetry of their cavities not only have large difference in these three types of pillar[5]arenes, but also have more or less variations even in the same structure type or the same host locked different guests such as crystals of 3a–3b, 4a–4d. On the other hand, the complexation behavior of pillar[5]arenes with 1,4-dibromobutane (DBB) is affected by the different symmetrical struct…

A facile and efficient preparation of pillararenes and a pillarquinone.

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