Reações de adição 1,2 a iminas: 1. síntese de triclorometilaminas e estudos mecanísticos por ATR-FTIR em tempo real; 2. síntese estereosseletiva de derivados de diaminoácidos via organocatálise

Abstract

1,2-addition reactions to imines are a synthetic tool of great interest for obtaining building blocks containing amine and amino acid scaffolds with pharmacological interest, agrochemical industry and other fine chemicals. Therefore, it is possible to access not only substrates for the synthesis of complex molecules but also compounds of relevant biological properties. Thus, we proposed two strategies for preparation of those compounds: first, the development of a methodology to obtain trichloromethylamines from the addition of the trichloromethyl anion generated by the decarboxylation of the potassium trichloroacetate salt under mild and economically viable conditions was presented. A diastereoselective version was presented to obtain an enantiomerically pure derivative. For a better understanding of the mechanism, kinetics of decarboxylation, and the formation of involved species, Fourier Transform Infrared spectroscopy with real attenuated Total Reflection (ATR-FTIR) was used. The data indicated the kinetics behavior, importance of the addition of the reagents as well as the formation of the -CCl3 anion. Second, the synthesis of α,β-diamino acid derivatives via asymmetric Brønsted acid catalyzed Mannich type reaction between azalactones and imines is also described. The chiral α,β-diamino acid derivatives were prepared in good yields and with near perfect diastereo- and enantioselectivities.