Síntese e dinâmica rotacional de [2]rotaxanos contendo 1-benzidrilpiperazina no eixo molecular

Abstract

This dissertation describes the synthesis of molecular the threads ((E)-1,4-bis(4-benzydrylpiperazin-1-yl)but-2-ene-1,4-dione, 1,4-bis(4-benzydrylpiperazin-1-yl)butan-1,4-dio ne, (E)-1,4-bis(dibutylamine)but-2ene-1,4-dione and 1,4-bis(dibutylamine)butan-1,4-dione) in order to obtain [2]rotaxanes molecules ([2]-[(E)-1,4-bis(4-benzydrylpiperazin-1-yl)but-2-en-1,4-dione]-rotaxa-[1,7,14,20-tetraaza-2,6,15,19-tetraoxo-3,5,9,12,16,18,22,25-tetrabenzocycl exacosane] and [2]-[1,4-bis(1,4-bis(4-benzydrylpiperazin-1-yl)butan-1,4-dione]-rotaxa-[1,7, 14,20-tetraaza-2,6,15,19-tetraoxo-3,5,9,12,16,18,22,25-te trabenzocycleexacosane]) having as common factor the presence of 1-benzhydrylpiperazine as stopper. In addition, it was proposed to synthesize a new class of [2]rotaxanes, containing an unprecedented tetralactam macrocycle, which contain a bicycle. The synthetic process goes through the synthesis of molecular threads, by means of an acyl nucleophilic substitution reaction, culminating in the formation of [2]rotaxane molecules, which were subjected to the clipping method in a multicomponent reaction. From the [2]rotaxanes obtained, there were yields between 7 – 22 %, however it was not possible to observe the formation of the [2]rotaxanes bearing bicycles in the macrocycle. The synthesized molecules were identified and characterized by 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy, in one and two-dimensional experiments, mass spectrometry, infrared spectroscopy and, in some cases, single crystal X-ray diffraction (SCXRD). The molecular environment of some compounds was studied in solution, by NMR techniques and in solid state, through the data obtained from the SCXRD. It was possible to determine the rotational energy barrier of two [2]rotaxanes by 1H NMR experiments with temperature variation.