19672-91-4Relevant academic research and scientific papers
Regioselective Synthesis of 2° Amides Using Visible-Light-Induced Photoredox-Catalyzed Nonaqueous Oxidative C-N Cleavage of N, N-Dibenzylanilines
Neerathilingam, Nalladhambi,Bhargava Reddy, Mandapati,Anandhan, Ramasamy
, p. 15117 - 15127 (2021/10/25)
A visible-light-driven photoredox-catalyzed nonaqueous oxidative C-N cleavage of N,N-dibenzylanilines to 2° amides is reported. Further, we have applied this protocol on 2-(dibenzylamino)benzamide to afford quinazolinones with (NH4)2S2O8 as an additive. Mechanistic studies imply that the reaction might undergo in situ generation of α-amino radical to imine by C-N bond cleavage followed by the addition of superoxide ion to form amides.
Regio- And Stereoselective (S N2) N -, O -, C - And S -Alkylation Using Trialkyl Phosphates
Banerjee, Amit,Hattori, Tomohiro,Yamamoto, Hisashi
, (2021/06/16)
Bimolecular nucleophilic substitution (S N 2) is one of the most well-known fundamental reactions in organic chemistry to generate new molecules from two molecules. In principle, a nucleophile attacks from the back side of an alkylating agent having a suitable leaving group, most commonly a halide. However, alkyl halides are expensive, very harmful, toxic and not so stable, which makes them problematic for laboratory use. In contrast, trialkyl phosphates are inexpensive, readily accessible and stable at room temperature, under air, and are easy to handle, but rarely used as alkylating agents in organic synthesis. Here, we describe a mild, straightforward and powerful method for nucleophilic alkylation of various N -, O -, C - and S -nucleophiles using readily available trialkyl phosphates. The reaction proceeds smoothly in excellent yield, and quantitative yield in many cases, and covers a wide range of substrates. Further, the rare stereoselective transfer of secondary alkyl groups has been achieved with inversion of configuration of chiral centers (up to 98% ee).
Preparation of alkylated compounds using the trialkylphosphate
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Paragraph 0184-0185; 0191, (2021/11/02)
[Problem] trialkylphosphate strong base used reaction agent, a carboxylic acid, a ketone, an aldehyde, amine, amide, thiol, ester or Grignard reagent to a variety of substrates, and/or high efficiency to generate a highly stereoselective alkylation reaction, the alkylated compounds capable of producing new means. [Solution] was used as the alkylating agent in the alkylation of compound trialkylphosphate, strongly basic reaction production use. [Drawing] no
IrIII-Catalyzed direct syntheses of amides and esters using nitriles as acid equivalents: A photochemical pathway
Talukdar, Ranadeep
supporting information, p. 5303 - 5308 (2020/04/17)
An unprecedented IrIII[df(CF3)ppy]2(dtbbpy)PF6-catalyzed simple photochemical process for direct addition of amines and alcohols to the relatively less reactive nitrile triple bond is described herein. Various amides and esters are synthesized as the reaction products, with nitriles being the acid equivalents. A mini-library of different types of amides and esters is made using this mild and efficient process, which uses only 1 mol% of photocatalyst under visible light irradiation (λ = 445 nm). The reaction strategy is also efficient for gram-scale synthesis.
Facile amidation of esters with aromatic amines promoted by lanthanide tris (amide) complexes
Li, Zhao,Guo, Chenjun,Chen, Jue,Yao, Yingming,Luo, Yunjie
, (2020/02/04)
The development of catalysts capable of catalyzing amidation of esters with amines to construct amides under mild conditions is of great importance. Compared to aliphatic amines, the direct catalytic amidation of esters with less nucleophilic aromatic amines is rather difficult. Employing simple lanthanide tris (amide) complexes Ln[N (SiMe3)2]3(μ-Cl)Li (THF)3 as the catalysts, it was found a broad range of aromatic amines and esters were efficiently converted into various amides in good yields under mild conditions. A plausible mechanism for this transformation was experimentally supported as starting from an amide exchange reaction between the lanthanide tris (amide) complex and the substrate amine.
Cross-Dehydrogenating Coupling of Aldehydes with Amines/R-OTBS Ethers by Visible-Light Photoredox Catalysis: Synthesis of Amides, Esters, and Ureas
Pandey, Ganesh,Koley, Suvajit,Talukdar, Ranadeep,Sahani, Pramod Kumar
supporting information, p. 5861 - 5865 (2018/09/21)
A straightforward synthesis of amides, ureas, and esters is reported by visible-light cross-dehydrogenating coupling (CDC) of aldehydes (or amine carbaldehydes) and amines/R-OTBS ethers by photoredox catalysis. The reaction is found to be general and high yielding. A plausible mechanistic pathway has been proposed for these transformations and is supported by appropriate controlled experiments.
Unexpected Rearrangement of 2-Bromoaniline under Biphasic Alkylation Conditions
Barraza, Scott J.,Denmark, Scott E.
, p. 2891 - 2895 (2017/10/06)
Alkylation of 2-bromoaniline with benzyl bromide under ostensibly basic N-alkylation conditions resulted in migration of bromine from the 2- to the 4-aryl position. Herein we report our studies to elucidate the mechanism of this rearrangement with the objective of suppressing this unexpected outcome. We find that careful choice of reagents is critical, and that this behavior may be extrapolated to alkylation reactions of electron-rich bromo- and iodoanilines in general.
An efficient and mild oxidative amidation of aldehydes using B(C6F5)3 as a catalyst and biological evaluation of the products as potential antimicrobial agents
Guggilapu, Sravanthi Devi,Chari, Alpina Ramnath,Nagarsenkar, Atulya,Sigalapalli, Dilep Kumar,Babu, Bathini Nagendra
, p. 2328 - 2332 (2017/03/21)
A mild and efficient protocol for oxidative amidation of diverse aldehydes with amines was developed using 3 mol% tris(pentafluorophenyl)borane and tert-butyl hydroperoxide to generate the corresponding amides in good to excellent yields. This method has significant advantages such as short reaction time, low toxicity, low catalyst loading, and being environmentally friendly and an operationally simple procedure. Acid labile protecting groups such as acyl and Boc displayed tolerance under the present catalytic system. Applicability in large scale synthesis of amides is an added advantage of the protocol. Moreover, direct amidation of aldehydes using substituted N-benzylanilines for the synthesis of corresponding amides was devised using the present catalytic system. Compounds 3n and 3o displayed promising antimicrobial activity against Staphylococcus aureus (Gram positive) with MIC ranging from 0.4-0.7 μg mL?1 and against Escherichia coli (Gram negative) with MIC 0.7-1.2 μg mL?1 with reference to the standard drug Ciprofloxacin.
Transition metal-free N-arylation of secondary amides through iodonium salts as aryne precursors
Wang, Ming,Huang, Zhijian
supporting information, p. 10185 - 10188 (2016/11/11)
By using a diaryliodonium salt as a benzyne precursor, a transition metal-free approach for N-arylation of secondary amides is developed. This novel benzyne precursor, which can be prepared easily by a one step process from an aryl iodide, shows different reactivities with previous benzyne precursors in the N-arylation reaction. Mechanistic studies confirm the involvement of benzyne species (generated in situ from the diaryliodonium salts) as key intermediates.
Iron-catalyzed oxidative amidation of tertiary amines with aldehydes
Li, Yuanming,Jia, Fan,Li, Zhiping
supporting information, p. 82 - 86 (2013/03/13)
Unconventional couple: A new oxidative coupling protocol for amide bond formation has been developed (see scheme). The method provides an efficient and practical route for the synthesis of tertiary amides from readily available tertiary amines and aldehydes in the presence of a simple FeCl2 catalyst. Mechanistic studies indicated that a peroxide and an iminium ion act as the reactive intermediates in this oxidative amidation.
