57149-81-2Relevant academic research and scientific papers
An efficient mechanochemical synthesis of amides and dipeptides using 2,4,6-trichloro-1,3,5-triazine and PPh3
Duangkamol, Chuthamat,Jaita, Subin,Wangngae, Sirilak,Phakhodee, Wong,Pattarawarapan, Mookda
, p. 52624 - 52628 (2015/06/25)
A rapid, facile, and efficient mechanochemical synthesis of amides from carboxylic acids has been developed through an in situ acid activation with 2,4,6-trichloro-1,3,5-triazine and a catalytic amount of PPh3. Under room temperature solvent-drop grinding of the reactants in the presence of an inorganic base, a variety of carboxylic acids including aromatic acids, aliphatic acids, and N-protected α-amino acids undergo amidation to afford amides in moderate to excellent yields. The method is also compatible with Fmoc, Cbz, and Boc protecting groups which yields protected optically active dipeptides without detectable racemization.
Copper-catalyzed intermolecular amidation and imidation of unactivated alkanes
Tran, Ba L.,Li, Bijie,Driess, Matthias,Hartwig, John F.
supporting information, p. 2555 - 2563 (2014/03/21)
We report a set of rare copper-catalyzed reactions of alkanes with simple amides, sulfonamides, and imides (i.e., benzamides, tosylamides, carbamates, and phthalimide) to form the corresponding N-alkyl products. The reactions lead to functionalization at secondary C-H bonds over tertiary C-H bonds and even occur at primary C-H bonds. [(phen)Cu(phth)] (1-phth) and [(phen)Cu(phth)2] (1-phth2), which are potential intermediates in the reaction, have been isolated and fully characterized. The stoichiometric reactions of 1-phth and 1-phth2 with alkanes, alkyl radicals, and radical probes were investigated to elucidate the mechanism of the amidation. The catalytic and stoichiometric reactions require both copper and tBuOOtBu for the generation of N-alkyl product. Neither 1-phth nor 1-phth2 reacted with excess cyclohexane at 100 C without tBuOOtBu. However, the reactions of 1-phth and 1-phth2 with tBuOOtBu afforded N-cyclohexylphthalimide (Cy-phth), N-methylphthalimide, and tert-butoxycyclohexane (Cy-OtBu) in approximate ratios of 70:20:30, respectively. Reactions with radical traps support the intermediacy of a tert-butoxy radical, which forms an alkyl radical intermediate. The intermediacy of an alkyl radical was evidenced by the catalytic reaction of cyclohexane with benzamide in the presence of CBr4, which formed exclusively bromocyclohexane. Furthermore, stoichiometric reactions of [(phen)Cu(phth)2] with tBuOOtBu and (Ph(Me)2CO) 2 at 100 C without cyclohexane afforded N-methylphthalimide (Me-phth) from β-Me scission of the alkoxy radicals to form a methyl radical. Separate reactions of cyclohexane and d12-cyclohexane with benzamide showed that the turnover-limiting step in the catalytic reaction is the C-H cleavage of cyclohexane by a tert-butoxy radical. These mechanistic data imply that the tert-butoxy radical reacts with the C-H bonds of alkanes, and the subsequent alkyl radical combines with 1-phth2 to form the corresponding N-alkyl imide product.
The scope and limitation of nickel-catalyzed aminocarbonylation of aryl bromides from formamide derivatives
Jo, Youngshin,Ju, Jinhun,Choe, Jaehoon,Kwang, Ho Song,Lee, Sunwoo
supporting information; experimental part, p. 6358 - 6361 (2009/12/08)
(Chemical Equation Presented) Nickel-catalyzed aminocarbonylation of aryl halides is described. A well-defined air-stable nickel-phosphite catalytic system (Ni(OAc)2 · 4H2O/phosphite 1) effectively promoted the aminocarbonylation of
One-step RhCl3-catalyzed deprotection of acyclic N-allyl amides
Zacuto, Michael J.,Xu, Feng
, p. 6298 - 6300 (2008/02/10)
(Chemical Equation Presented) A convenient one-step RhCl 3-catalyzed deprotection of acyclic N-allyl amides is described. Preliminary mechanistic studies reveal that the key to the success of the one-step deprotection process is the dual function of RhCl3 in alcohol solvents. Reaction of RhCl3 with n-PrOH not only provides an active rhodium hydride species to catalyze isomerization of N-allyl amides to corresponding enamides but also generates a crucial catalytic amount of HCl to convert the enamides to deallylated amides through N,O-acetal exchange.
