16466-44-7Relevant academic research and scientific papers
Nickel-Catalyzed Oxidative Transamidation of Tertiary Aromatic Amines with N -Acylsaccharins
Liu, Shengzhang,Yang, Lingyun,Tao, Jiasi,Yu, Weijie,Wang, Tao,Fu, Junkai
supporting information, p. 1642 - 1646 (2021/06/21)
The use of tertiary amines as surrogates for secondary amines has prominent advantages in terms of stabilization and ease of handling. A Ni-catalyzed transamidation of N -acylsaccharins with tertiary aromatic amines is reported. By using tert -butyl hydroperoxide as the terminal oxidant, this reaction permits selective cleavage of the C(sp 3)-N bonds of unsymmetrical tertiary aromatic amines depending on the sizes of the alkyl substituents.
Pd-Catalyzed Oxidative Aminocarbonylation of Arylboronic Acids with Unreactive Tertiary Amines via C-N Bond Activation
Kolekar, Yuvraj A.,Bhanage, Bhalchandra M.
, p. 14028 - 14035 (2021/05/29)
An efficient synthesis of tertiary amides from aryl boronic acids and inert tertiary amines through the oxidative carbonylation via C(sp3)-N bond activation is presented. This protocol significantly restricts the homocoupling biarylketone product. It involves the use of a homogeneous PdCl2/CuI catalyst and a heterogeneous Pd/C based catalyst, which promotes C(sp3)-N bond activation of tertiary amines with aryl boronic acids. This process represents a ligand-free, base-free, and recyclable catalyst along with an ideal oxidant like molecular oxygen.
Preparation of alkylated compounds using the trialkylphosphate
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Paragraph 0184-0186, (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
Palladium-Catalyzed Desulfurative Hiyama Coupling of Thioureas to Achieve Amides via Selective C-N Bond Cleavage
He, Zhanyu,Yan, Chu,Zhang, Mei,Irfan, Majeed,Wang, Zijia,Zeng, Zhuo
supporting information, p. 705 - 710 (2021/10/25)
Palladium-catalyzed Hiyama coupling of active thioureas via selective C-N bond cleavage is reported. Notably, the new approach employed active thioureas as coupling partners in the presence of arylsilanes to give amides in good yield. Further, this strategy, which utilized CuF 2as a key oxidant and activator, afforded various amide products under mild conditions and an easy to handle procedure without extra base.
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).
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.
Frustrated Lewis Pair Catalyzed Hydrogenation of Amides: Halides as Active Lewis Base in the Metal-Free Hydrogen Activation
Sitte, Nikolai A.,Bursch, Markus,Grimme, Stefan,Paradies, Jan
supporting information, p. 159 - 162 (2019/01/04)
A method for the metal-free reduction of carboxylic amides using oxalyl chloride as an activating agent and hydrogen as the final reductant is introduced. The reaction proceeds via the hydrogen splitting by B(2,6-F2-C6H3)3 in combination with chloride as the Lewis base. Density functional theory calculations support the unprecedented role of halides as active Lewis base components in the frustrated Lewis pair mediated hydrogen activation. The reaction displays broad substrate scope for tertiary benzoic acid amides and α-branched carboxamides.
KMnO4-mediated oxidative C[sbnd]N bond cleavage of tertiary amines: Synthesis of amides and sulfonamides
Zhang, Zhang,Liu, Yong-Hong,Zhang, Xi,Wang, Xi-Cun
, p. 2763 - 2770 (2019/04/10)
KMnO4-mediated oxidative C[sbnd]N bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.
Highly Chemoselective, Transition-Metal-Free Transamidation of Unactivated Amides and Direct Amidation of Alkyl Esters by N-C/O-C Cleavage
Li, Guangchen,Ji, Chong-Lei,Hong, Xin,Szostak, Michal
supporting information, p. 11161 - 11172 (2019/08/07)
The amide bond is one of the most fundamental functional groups in chemistry and biology and plays a central role in numerous processes harnessed to streamline the synthesis of key pharmaceutical and industrial molecules. Although the synthesis of amides is one of the most frequently performed reactions by academic and industrial scientists, the direct transamidation of tertiary amides is challenging due to unfavorable kinetic and thermodynamic contributions of the process. Herein, we report the first general, mild, and highly chemoselective method for transamidation of unactivated tertiary amides by a direct acyl N-C bond cleavage with non-nucleophilic amines. This operationally simple method is performed in the absence of transition metals and operates under unusually mild reaction conditions. In this context, we further describe the direct amidation of abundant alkyl esters to afford amide bonds with exquisite selectivity by acyl C-O bond cleavage. The utility of this process is showcased by a broad scope of the method, including various sensitive functional groups, late-stage modification, and the synthesis of drug molecules (>80 examples). Remarkable selectivity toward different functional groups and within different amide and ester electrophiles that is not feasible using existing methods was observed. Extensive experimental and computational studies were conducted to provide insight into the mechanism and the origins of high selectivity. We further present a series of guidelines to predict the reactivity of amides and esters in the synthesis of valuable amide bonds by this user-friendly process. In light of the importance of the amide bond in organic synthesis and major practical advantages of this method, the study opens up new opportunities in the synthesis of pivotal amide bonds in a broad range of chemical contexts.
Direct Synthesis of Amides from Oxidative Coupling of Benzyl Alcohols and N-substituted Formamides Using a Co–Al Based Heterogeneous Catalyst
Subhedar, Dnyaneshwar D.,Gupta, Shyam Sunder R.,Bhanage, Bhalchandra M.
, p. 3102 - 3111 (2018/08/21)
Present work reports the direct synthesis of amides from oxidative coupling of benzyl alcohols with various N-substituted formamides using a cobalt-hydrotalcite (Co-HT) derived catalyst. The Co-HT derived catalysts (Co-HT-2, Co-HT-3 and Co-HT-4 having Co2+/Al3+ molar ratio in the catalyst preparation mixture as 1/1, 2/1 and 3/1 respectively) were prepare following a co-precipitation method and characterized well by powder XRD, XPS, FEG-SEM, EDS, DTG–TGA, FT-IR and N2 physisorption measurements. A range of functional amides were obtained in good yields from oxidative coupling of various substituted benzyl alcohols and a range of N-substituted formamides using Co-HT-3 catalyst and oxidant TBHP. Mechanistic investigation suggests that the amidation reaction is associated with the formation and coupling of radical species. Furthermore, the Co-HT derived catalyst was easily recoverable and recyclable with retained high catalytic activity towards the oxidative coupling of benzyl alcohol with DMF. Graphical Abstract: [Figure not available: see fulltext.].
