Experimental and theoretical studies on cycloaddition (3 + 2) reactions of azides to nitro-olefins

• Grant number: 17/01754-0
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): May 01, 2017
• Status: Discontinued
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Cooperation agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Marco Antonio Barbosa Ferreira
• Grantee: Meire Yasuko Kawamura
• Home Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 15/08541-6 - Nuclear magnetic resonance spectroscopy: beyond molecular structure assignment, AP.TEM
• Associated scholarship(s): 19/14609-3 - Dynamics behavior in the border area between concerted syn-elimination (EI) and stepwise elimination (E1), BE.EP.DR

Abstract

Nitroolefins have emerged as important building blocks for the synthesis of 1,2,3-triazoles, representing an important advance in the search for more efficient and selective alternatives of these units. Several types of reactional systems have been used highlighting the possibility of direct use of sodium azides (leading to the preparation of 1H-1,2,3-triazoles) as well as substituted azides and nitroolefins which may give substituted 1,2,3-triazoles. With the introduction of organocatalysis and metal catalysis in these systems, the control of the regioselectivity of this reaction has been described. However, up to the present moment, no reasoned mechanistic proposal has been described so far, justifying the proposed work proposal. Moreover, as will be shown, access to the 1,4-regioisomer is still unprecedented from nitroolefins. Therefore, one of the aspects of this work is to investigate the cycloaddition reaction (3 + 2) of nitroolefins under "metal-free" conditions. A systematic study will lead to the preparation of 1,4-disubstituted 1,2,3-triazoles by the use of alpha-nitroolefins. In another aspect of the work, we will use computational techniques and kinetic studies (including KIE, speed law determination, etc.) to elucidate the mechanistic processes under "catalyst-free" conditions, organocatalysis Brønsted), among others, of this reaction clarifying its reactivity and selectivity against the different reaction conditions. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ECHEMENDIA, RADELL; DA SILVA, GUSTAVO P.; KAWAMURA, MEIRE Y.; DE LA TORRE, ALEXANDER F.; CORREA, ARLENE G.; FERREIRA, MARCO A. B.; RIVERA, DANIEL G.; PAIXAO, MARCIO W. A stereoselective sequential organocascade and multicomponent approach for the preparation of tetrahydropyridines and chimeric derivatives. CHEMICAL COMMUNICATIONS, v. 55, n. 3, p. 286-289, JAN 11 2019. Web of Science Citations: 3.