Ionic Liquids and the Heck Coupling Reaction: An Update

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)In this review update we provide a critical analysis of recent results concerning the use of ionic liquids (ILs) as viable, effective, and environmental friendly media for the Heck reactions (HR). The examples selected illustrate the multifaceted action of ILs as nanoparticles stabilizers, promoters of ligand-assisted HR, promoters of phosphine-free HR, solvent for the Heck-Matsuda reactions employing arenediazonium salts, in the dehydrative Heck olefination, and as charged-tagged pre-catalysts. These selected reports aim at demonstrating the scope and the impact of Ils on new discoveries, as well as to illustrate the new opportunities and challenges they offer for those interested in catalysis and organic synthesis in general.173238256Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Non-occurrence Of A Zincke-like Process Upon Treatment Of 1-(2,4-dinitrophenyl)-3-methylimidazolium Chloride With A Chiral Primary Amine

Huang's preparation of chiral imidazolium salts by means of a Zincke-like process was re-investigated. It was shown that treatment of 1-(2,4- dinitrophenyl)-3-methylimidazolium chloride with l-alaninol gives rise to complete decomposition of the starting salt via an SNAr reaction and that the material described by Huang was not the claimed chiral imidazolium salt, thus questioning the occurrence of the ionic liquids reported in the original work. © The Royal Society of Chemistry.108885889Génisson, Y., Marazano, C., Mehmandoust, M., Gnecco, D., Das, B.C., (1992) Synlett, 46, p. 431. , -434Viana, G.H.R., Santos, I.C., Alves, R.B., Gil, L., Marazano, C., Gil, R.P.F., (2005) Tetrahedron Lett., 46, p. 7773. , -7776Nguyen, T.M., Del Rayo Sanchez-Salvatori, M., Wypych, J.-C., Marazano, C., (2007) J. Org. Chem., 72, p. 5916. , Selected references: -5919Génisson, Y., Marazano, C., Das, B.C., (1993) J. Org. Chem., 58, p. 2052. , -2057Wong, Y.-S., Marazano, C., Gnecco, D., Génisson, Y., Chiaroni, A., Das, B.C., (1997) J. Org. Chem., 62, p. 729. , -733Compere, D., Marazano, C., Das, B.C., (1999) J. Org. Chem., 64, p. 4528. , -4532Gil, L., Compere, D., Guilloteau-Bertin, B., Chiaroni, A., Marazano, C., (2000) Synthesis, p. 2117. , -2126Guilloteau-Bertin, B., Compere, D., Gil, L., Marazano, C., Das, B.C., (2000) Eur. J. Org. Chem., p. 1391. , -1399Patrascu, C., Sugisaki, C., Mingotaud, C., Marty, J.-D., Génisson, Y., Lauth-De Viguerie, N., (2004) Heterocycles, 63, p. 2033. , -2041Ou, W.-H., Huang, Z.-Z., (2006) Green Chem., 8, p. 731. , -734Génisson, Y., Lauth-De Viguerie, N., André, C., Baltas, M., Gorrichon, L., (2005) Tetrahedron: Asymmetry, 16, p. 1017. , -1023Ogata, Y., Okano, M., (1949) J. Am. Chem. Soc., 71, p. 3211. , -3212Bao, W., Wang, Z., Li, Y., (2003) J. Org. Chem., 68, p. 591. , -59

Substrate-Directable Heck Reactions with Arenediazonium Salts. The Regio- and Stereoselective Arylation of Allylamine Derivatives and Applications in the Synthesis of Naftifine and Abamines

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The palladium-catalyzed, substrate-directable Heck-Matsuda reaction of allylamine derivatives with arenediazonium salts is reported. The reaction proceeds under mild conditions, with excellent regio- and stereochemical control as a function of coordinating groups present in the allylamine substrate. The distance between the olefin moiety and the carbonylic system seems to play a key role regarding the regiocontrol. The method presents itself as robust, as simple to carry out, and with wide synthetic scope concerning the allylic substrates and the type of arenediazonium employed. The synthetic potential of the method is illustrated by the short total syntheses of the bioactive compounds naftifine, abamine, and abamine SG.761977377749Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Non-occurrence of a Zincke-like process upon treatment of 1-(2,4-dinitrophenyl)-3-methylimidazolium chloride with a chiral primary amine

Huang's preparation of chiral imidazolium salts by means of a Zincke-like process was re-investigated. It was shown that treatment of 1-(2,4-dinitrophenyl)-3-methylimidazolium chloride with L-alaninol gives rise to complete decomposition of the starting salt via an S(N)Ar reaction and that the material described by Huang was not the claimed chiral imidazolium salt, thus questioning the occurrence of the ionic liquids reported in the original work.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.10888588