Direct Nickel‐Catalyzed Amination of Phenols via CO Bond Activation using 2,4,6‐Trichloro‐1,3,5‐triazine (TCT) as Reagent

Abstract

2,4,6-Trichloro-1,3,5-triazine (TCT) was used as an efficient and mild reagent for the direct nickel-catalyzed amination of phenols. This reagent can promote amination of phenols via the activation of the phenolic C À O bond. In this simple protocol, the in situ generated aryl C À O electrophile (Ar-O-TCT) reacts with the desired amine to produce the corresponding arylamine in the presence of a nickel catalyst. This strategy is general for a variety of substrates to give the related arylamines in moderate to good yields. This method was also applied for nickel-catalyzed amination of phenols for the synthesis of primary aromatic amines using the reaction of Ar-O-TCT and ammonium carbonate under mild reaction conditions. With this method, phenolic compounds are converted to their corresponding anilines under mild conditions.

Chitosan‐Supported Ni particles: An Efficient Nanocatalyst for Direct Amination of Phenols

“…The reaction mechanism for this reaction is suggested based on reported procedure . In all likelihood, the nickel metal can coordinate with ortho nitrogen atom of 2,4,6‐triaryloxy‐1,3,5‐triazine and this conveniences the oxidative addition in which Ni inserts into the C‐O bond to produce Ni (II) intermediate.…”

“…Furthermore, the insolubility of chitosan in common solvents explains the potential of chitosan as suitable supports for various reagents and catalysts . Recently, Iranpoor et al reported amination of phenols using (TCT) as an efficient promotor under homogeneous catalytic system applying various Ni sources and ligands . We recently reported an interesting chitosan based nickel nanocatalyst which were synthesized via ‘click’ reaction of an alkynlated imino‐ thiophene ligand with azide functionalized chitosan for application in Suzuki reaction.…”

Buchwald–Hartwig amination reaction using supported palladium on phosphine-functionalized magnetic nanoparticles

“…Since the discovery of the BHAR (1995) [10,11], a range of modifications for this reaction has been developed to increase the reaction efficacy [12,13]. A survey in this field demonstrated that major advances have been obtained on developing new and more effective phosphorus ligands.…”

Arylation of Aniline C(sp3)−H Bonds with Phenols via an In Situ Activation Strategy

“…[5] Alternatively, the cross couplings of phenols via in situ generation of activated electrophiles received much attention to avoid purification with higher step efficiency and time economy. [6][7][8] Notably,a pplications of this strategy in the arylation of CÀHb onds shows even greater impact to avoid using stoichiometric organometallic reagents (Scheme 1). [9] For example, Vand er Eycken, Kang and Aldrich independently designed Sonogashira-type reactions to forge C(sp)ÀC(sp 2 )b onds via in situ generation of organic phenolic phosphonium salts.…”

“…Following that, we screened ar ange of activation reagents that were previously reportedt oa ctivate phenols, such as PhB(OH) 2 ,E t 3 B, (PhO) 2 P(O)Cl, AcCl andP yBroP (Table 1, entries 2-6). [4][5][6][7][8] However,n oc oupling product could be detected. To our delight, the desired product 3aa was obtained in 75 %y ield by using TsCl as an activation reagent (Table 1, entry 7).…”