基于配体调控通过金属配位实现自组装同腔或异腔笼的完整选择。

Complete selection of a self-assembling homo- or hetero-cavitand cage via metal coordination based on ligand tuning.

作者信息

Kobayashi Kenji, Yamada Yoshifumi, Yamanaka Masamichi, Sei Yoshihisa, Yamaguchi Kentaro

机构信息

Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.

出版信息

J Am Chem Soc. 2004 Nov 3;126(43):13896-7. doi: 10.1021/ja0465799.

DOI:10.1021/ja0465799

PMID:15506730

Abstract

Selective formation of a homo- or hetero-cavitand cage via metal-coordination, by using tetra(4-pyridyl)-cavitand (1), tetrakis(4-pyridylethynyl)-cavitand (2), or tetrakis(4-cyanophenyl)-cavitand (3) as deep cavitand ligands and Pd(dppp)(OTf)2 (4) as a connector, has been investigated by 1H NMR and CSI-MS. When the cavitand and 4 were mixed in CDCl3 in a 2:4 molar ratio, 1 gave a complicated mixture, whereas 2 or 3 formed a homo-cavitand cage {2(2).4[Pd(dppp)]}8+.8(TfO-) (5) or {2(3).4[Pd(dppp)]}8+.8(TfO-) (6), respectively, as a single species. In a 1:1:4 mixture of 2, 3, and 4, homo-cavitand cages 5 and 6 were observed in a 1:1 ratio. In marked contrast, a mixture of 1, 3, and 4 in a 1:1:4 ratio was exclusively self-assembled into a hetero-cavitand cage {1.3.4[Pd(dppp)]}8+.8(TfO-) (7). The selectivity for the self-assembly of the homo- or hetero-cavitand cage via metal coordination would arise from a combination of factors such as coordination ability and steric demand of cavitand ligands.

摘要

通过使用四（4 - 吡啶基）- 穴番（1）、四（4 - 吡啶基乙炔基）- 穴番（2）或四（4 - 氰基苯基）- 穴番（3）作为深穴番配体以及Pd(dppp)(OTf)₂（4）作为连接体，通过¹H NMR和CSI - MS研究了通过金属配位选择性形成同穴番笼或异穴番笼的情况。当穴番和4以2:4的摩尔比在CDCl₃中混合时，1产生复杂混合物，而2或3分别形成单一物种的同穴番笼{2(2).4[Pd(dppp)]}⁸⁺.8(TfO⁻)（5）或{2(3).4[Pd(dppp)]}⁸⁺.8(TfO⁻)（6）。在2、3和4的1:1:4混合物中，观察到同穴番笼5和6的比例为1:1。形成鲜明对比的是，1、3和4以1:1:4比例的混合物专门自组装成异穴番笼{1.3.4[Pd(dppp)]}⁸⁺.8(TfO⁻)（7）。通过金属配位自组装同穴番笼或异穴番笼的选择性将源于穴番配体的配位能力和空间需求等多种因素的组合。