A V-EASI-MS Study of the Ugi Reaction Mechanism

A V-EASI-MS Study of the Ugi Reaction Mechanism

Santos, Vanessa G.; Regiani, Thais; Eberlin, Marcos N.; Garden, Simon J.; Gama, Fernando H. de Souza; Miranda, Leandro Soter de Mariz e; Souza, Rodrigo Octávio Mendonça Alves de

Abstract:

Multicomponent reactions are defined as those where more then two substances react and essencially most of their atoms are incorporated in the product. In the case of the Ugi four component reaction an isocyanide, aldehyde, amine and carboxylic acid react to form a tripeptide. One important characteristic of the multicomponent reaction is the difficulty to elucidate the molecular sequence of events that take place in order to form the products. Venturi easy ambient sonic-spray ionization (VEASI) 1 is an ambient ionization technique based on the Venturi effect that provides self-pumping and online monitoring of the Ugi reaction giving representative snapshots of the ionic composition of the reaction solution and therefore key information with respect to the mechanism(s). In this study, we have used V-EASI and charged tagged reagents with a remote quaternary ammonium functionality to improve detection of otherwise neutral or zwitterionic species. The model reaction employed 4- trimethylammonium benzaldeyde iodide, acetic acid, aniline and cyclohexylisocyanide, in equimolar quantities and at ambient temperature in methanol.

Multicomponent reactions are defined as those where more then two substances react and essencially most of their atoms are incorporated in the product. In the case of the Ugi four component reaction an isocyanide, aldehyde, amine and carboxylic acid react to form a tripeptide. One important characteristic of the multicomponent reaction is the difficulty to elucidate the molecular sequence of events that take place in order to form the products. Venturi easy ambient sonic-spray ionization (VEASI) 1 is an ambient ionization technique based on the Venturi effect that provides self-pumping and online monitoring of the Ugi reaction giving representative snapshots of the ionic composition of the reaction solution and therefore key information with respect to the mechanism(s). In this study, we have used V-EASI and charged tagged reagents with a remote quaternary ammonium functionality to improve detection of otherwise neutral or zwitterionic species. The model reaction employed 4- trimethylammonium benzaldeyde iodide, acetic acid, aniline and cyclohexylisocyanide, in equimolar quantities and at ambient temperature in methanol.

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DOI: 10.5151/chempro-14bmos-R0137-2

Referências bibliográficas

• [1] 1 Santos, V. G.; Regiani, T.; Dias, F. F. G.; Romão, W.; Jara, J. L. P.; Klitzke, C. F.; Coelho, F.; Eberlin, M. N. Venturi Easy Ambient Sonic-Spray Ionization. Anal. Chem,, 2011, 83 (4), pp 1375-1380
• [2] 2 Ramzi Ait Youcef, Mickael Dos Santos, Sandrine Roussel, Jean-Pierre Baltaze, Nadege Lubin-Germain and Jacques Uziel. . Org. Chem., 2009, 74 (11), pp 4318–4323

Como citar:

Santos, Vanessa G.; Regiani, Thais; Eberlin, Marcos N.; Garden, Simon J.; Gama, Fernando H. de Souza; Miranda, Leandro Soter de Mariz e; Souza, Rodrigo Octávio Mendonça Alves de; "A V-EASI-MS Study of the Ugi Reaction Mechanism", p-137-137. In: In Blucher Chemistry Proceedings, São Paulo, v. 1, n. 1, Setembro.2013. São Paulo: Blucher, 2013.
ISSN 23184043, DOI 10.5151/chempro-14bmos-R0137-2