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[摘要]：Arc-shaped oligophenyl derivs. with terminal alkene moieties can be used to form macrocycles by dimerization through ring-closing metathesis. Hereby, the introduction of templates connecting the 2 building blocks favors dimerization over oligomerization or polymn. Attachment of the template through imine formation allows the removal of the template simultaneous to the redn. of the double bonds formed during ring-closing metathesis. Unsym. macrocylces can be obtained either by successive attachment of different arc-shaped mols. to the template or by direct imine connection of 2 different ring precursors. In the latter case, the imine unit cannot be cleaved in the case of the investigated examples but eight-shaped macrobicycles are obtained. The studied template-directed macrocyclization depends on the one hand on the preorganization of the building blocks, and on the other on their flexibility. |
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