Synthesis and Application of Calixarene(New Host Compound)-based Functional Molecules

在杯芳烃空腔的上边缘或下边缘合成了具有磺酸基的水溶性杯芳烃。这些co，pounds可以与各种有机分子形成主客型配合物，并具有基于“孔大小选择性”的分子识别能力。当脂肪族基团被引入到羟基中时，它们成为一类具有分子识别能力的新型表面活性剂。其中，邻十二烷基磺酰基芳烃形成单分子胶束，在水中具有较强的增溶能力。以水-双杯芳烃为原料合成手性杯芳烃。他们显示了客体分子加入后CD光谱的变化。这种变化归因于构象从“交替”到“锥形”的变化。这证实了“锥”杯芳烃提供的腔体更适合与“交替”杯芳烃结合。水溶性杯杯芳烃和杯杯芳烃衍生物与铀酰离子（UO_2^<2+>）形成稳定配合物，稳定常数为10^<18> - 10^<19> M^<-1>。此外，UO_2^<2+>对其他金属阳离子的选择性因子大于10^<12>。这些杯芳烃具有显著的结合常数和选择性因子，这是由于它们为与UO_2^<2+>形成配合物而预先组织的特殊结构所致。最后，测定了水溶性杯芳烃中羟基的4个pKa值。PK_<a1>（第一次解离）值为0 ~ 1，PK_<a4>（最后一次解离）值为12 ~ 16。这一发现支持了杯芳烃分子中有一个超酸性质子和一个超碱性氧阴离子。这是由于氢氧根之间有很强的氢键。这些结果表明杯芳烃可以作为设计新型配体、表面活性剂、催化剂和宿主分子的基本骨架。

Water-soluble calixarenes beaing the sulfonate groups either on the upper rim or on the loaer rim of the calixarene cavity were synthesized. These co,pounds can form host-guest-type complexes with various organic molecules and are capable of molecular recognition on the basis of the "hole-size selectivity". When aliphatic groups were introduced into the OH groups, they acted as a new class of usrfactants with the molecular recognition ability. In particula, O-dodecyl-psulfonatocalix[6]arene formed the unimolecular micelle and should a strong solubilization power in water.Chiral calixarenes were synthesized from the water-doluble calixarenes. They showed the CD spectral change upon inclusion of guest molecules. This change was sttributed to the conformational change from "alternate" to "cone". This established that the "cone" calixarene provide the cavity more suitable to the guest-binding the "alternate" calixarene.water-soluble calix[5]arene and calix(6)arene derivatives formed the stable complexes with uranyl ion (UO_2^<2+>), the stability constans being 10^<18> - 10^<19> M^<-1>. Furthermore, the selectivity factors for UO_2^<2+> vs. other metal cations were greater than 10^<12>. The remarkably large binding constants and the selectivity factors are due to the specific architecture of these calixarenes preorganized for the complex formation with UO_2^<2+>. Finally, four pKa values of the OH groups in water-soluble calix[4]arenes were deternined. The PK_<a1> (first dissociation) values were 0-1 while the PK_<a4> (1ast dissociation) values aere 12-16. The finding supports that calixarenes have a super-acidic proton and a super-basic oxyanion withina amolecule. This is due to the storng hydrogen-bonding among the OH groups.These results show that calixarenes serve as a basic skeleton to design novel ligands, surfactants, catalusts, and host molecules.