Co(porphyrin)-catalysed amination of 1,2-dihydronaphthalene derivatives by aryl azides

Selective radical amination of aldehydic C(sp2)–H bonds with fluoroaryl azides via Co(ii)-based metalloradical catalysis: synthesis of N-fluoroaryl amides from aldehydes under neutral and nonoxidative conditions

“…19–20 Accordingly, the current catalytic process of intermolecular aldehydic C–H amination with fluoroaryl azides is supposed to undergo a similar stepwise radical mechanism (Figure 2). To obtain direct evidence for the proposed mechanism, we first sought to measure the deuterium kinetic isotope effect (KIE) for the reaction of benzaldehyde ( 1a ) with pentafluorophenyl azide ( 2a ) by [Co( P1 )] (Scheme 1).…”

“…19–20 Recently, Co(II)-based metalloradical catalysis (MRC) was successfully applied for asymmetric olefin aziridination with fluoroaryl azides as effective nitrene sources. 21 The Co(II)-catalyzed aziridination was believed to proceed through Co(III)-nitrene radical A as the key intermediate (Figure 2), which undergoes radical addition to olefin, followed by 3-exo-tet radical cyclization.…”

Uncatalyzed Oxidative C−H Amination of 9,10‐Dihydro‐9‐Heteroanthracenes: A Mechanistic Study

“…[1] Direct (sp 3 ) CÀHa mination viam etal-nitrene intermediatesh as received increasing attentioninthe last twodecades,asnopre-functionalization of theh ydrocarbon substratesi sr equired. [2][3][4][5] Keyd evelopmentsa re theu se of activated [6][7][8] andn on-activated organic azides, [9][10][11][12][13][14][15] Haloamine-T [16,17] and( in situ generated) iminoiodanes( PhI = NR)a sn itrene precursors (Figure1). [18][19][20][21][22][23] Transitionmetalc omplexes have proven to be excellentc atalysts fort hese aminationr eactions,a nd thec ommonlya cceptedm echanism comprisest he formationo fareactive metal-nitrenei ntermediate, followed by stepwise hydrogen atom abstractiona nd radicalr ecombination or concertedi nsertion of then itrene into the CÀHb ond.…”

The Research on Porphyrins and Analogues in Brazil: A Small Review Covering Catalytic and other Applications since the Beginning at Universidade de São Paulo in Ribeirão Preto until the Joint Venture between Brazilian Researchers and Colleagues from Universidade de Aveiro, Portugal

“…26 The ability of porphyrin's tetrapyrrolic core to accommodate metal ions of varying charges can modulate the type of application of these compounds. 27 For example, cobalt porphyrins were described as catalysts for the amination of 1,2-dihydronaphthalene derivatives, 28 ruthenium porphyrins in the enantio-and regioselective epoxidation of olefinic double bonds in quinolones, pyridones and amides 29 and in cyclopropanation and amination reactions; 30 nickel porphyrins as electrocatalyts of water oxidation to O 2 ; 31 and many others such as tin, zirconium, titanium and aluminum. [32][33][34][35][36][37] In the field of catalysis, synthetic metalloporphyrins, mainly the complexes with Mn III and Fe III ions, proved able to successfully oxidize hydrocarbons and other organic compounds under mild conditions.…”