Troger's base was the first amine to be resolved where the chirality was due to solely very high inversion barrier around nitrogen atom. Though the molecule was known for over a century, work done during the past decade has shown that Troger's base and its analogues could be used as chiral solvating agent, DNA binding ligand and for the construction of biomimetic molecular receptors and clathrare hosts. Asymmetric synthesis of the Troger’s base analogues has also been achieved recently. Because of the rigid, 'V'-shaped chiral nature of this molecule, there is growing interest for the use of this unit in the design of potential host systems. This section briefly describes the chemistry of Troger's base developed over a century.

Orientador: Fernando Antonio Santos Coelho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-15T03:19:35Z (GMT). No. of bitstreams: 1 Abella_CarlosAlbertoMiranda_D.pdf: 8234084 bytes, checksum: 0320b741bad5e28b8ad206ec73935836 (MD5) Previous issue date: 2009 / Resumo:O capítulo 1 relata os intermediários atingidos visando à síntese do alcalóide (±)-8-a-etoxiprecrivelina. Obteve-se um intermediário com todos os grupos funcionais necessários para atingir o alvo. A adição de metilamina sobre o aduto de Morita-Baylis-Hillman sililado proveniente do bromopiperonal levou ao produto de adição syn com elevada diastereosseletividade que foi racionalizada através de cálculos teóricos. Através de uma mudança na rota sintética inicialmente proposta, foi possível inserir um álcool secundário necessário através de uma reação de ozonólise seguida de redução quimiosseletiva. Dada a ausência na literatura deste tipo de reação sobre olefinas de adutos de Morita-Baylis-Hillman com anéis aromáticos, realizaram-se testes com adutos possuindo diferentes demandas eletrônicas no anel aromático os quais foram obtidos na sua maioria com sucesso. O capítulo 2 descreve a aplicação de uma metodologia desenvolvida no nosso grupo de pesquisa visando a síntese de alcalóides indolizidínicos a partir de lactamas bicíclicas polifuncionalizadas. Estas últimas foram obtidas nas suas formas racêmicas e quiral. O aldeído quiral sintetizado não racemizou nas condições empregadas na síntese do aduto de Morita-Baylis-Hillman, o qual foi obtido de forma majoritária como anti. Os diastereoisômeros foram separados e o majoritário ciclizado para fornecer a lactama bicíclica. A primeira parte do capítulo 3 relata as tentativas de usar bases de Tröger como catalisadores na reação de Morita-Baylis-Hillman, as quais se mostraram infrutíferas. Na segunda parte do mesmo capítulo, o mecanismo de reação de formação de bases de Tröger foi estudado por ESI-MS usando tanto formaldeído como urotropina como fontes de metileno. Os intermediários chaves foram caracterizados via ESI-MS/MS e determinou-se que o mecanismo envolve uma seqüência de reações de substituição eletrofílica aromática / Abstract: Chapter 1 describes the intermediates obtained towards the total synthesis of (±)-8-a-ethoxyprecriwelline. An intermediate with all required functionalities was obtained in order to achieve the target. Methylamine addition on silylated Morita-Baylis-Hillman adduct obtained from bromopiperonal gave mostly the syn diastereoisomer which was rationalized by the use of theoretical calculations. By means of changing the original synthetic proposal, it was possible to introduce a necessary secondary alcohol through an ozonolysis reaction followed by chemoselective reduction. Since there was no evidence of this kind of reaction on olefin of Morita-Baylis-Hillman adducts with aromatic ring in the literature, some test were done with adducts having different electronic requirements on the aromatic ring, and most were successfully obtained. Chapter 2 shows the application of a methodology developed in our research group envisaging the synthesis of indolizidinic alkaloids from polyfunctionalized bicyclic lactams. The latter were obtained in its racemic and chiral form. The chiral aldehyde synthesized didn' t racemize in the conditions used in the synthesis of Morita-Baylis-Hillman adduct, which was obtained as the anti as the major diastereomer. Both diastereomers were separated and the major one was cyclized to produce the bicyclic lactam. The first part of chapter 3 tells the tentative of use of Tröger' s bases as catalyst in the reaction of Morita-Baylis-Hillman, which didn' t prove useful. In the second part of the same chapter, the mechanism of formation of Tröger' s bases was studied by ESI-MS using formaldehyde as well as urotropine as the source of methylene. Key intermediates were characterized by ESI-MS/MS and it was found that the mechanism involves a sequence of electrophilic aromatic substitution reaction / Doutorado / Quimica Organica / Doutor em Ciências