1236981-85-3Relevant academic research and scientific papers
Ruthenium-catalyzed direct α-alkylation of amides using alcohols
Chaudhari, Moreshwar Bhagwan,Bisht, Girish Singh,Kumari, Pooja,Gnanaprakasam, Boopathy
, p. 9215 - 9220 (2016)
The highly efficient direct α-alkylation of unactivated amides has been accomplished using alcohols in the presence of the Ru-PNN catalyst (0.1 mol%) with a high turnover number. Using this approach, 2-oxindole was directly transformed into C3-alkylated 3-hydroxyindolin-2-one in one step without the use of any oxidant.
Nickel-catalyzed: C-alkylation of thioamide, amides and esters by primary alcohols through a hydrogen autotransfer strategy
Yang, Peng,Wang, Xiuhua,Ma, Yu,Sun, Yaxin,Zhang, Li,Yue, Jieyu,Fu, Kaiyue,Zhou, Jianrong Steve,Tang, Bo
supporting information, p. 14083 - 14086 (2020/11/20)
A simple catalyst of Ni(OAc)2 and P(t-Bu)3 enables selective C-alkylation of thioacetamides and primary acetamides with alcohols for the first time. Monoalkylation of thioamides, amides and t-butyl esters occurs in excellent yields (>95%). Mechanistic studies reveal that the reaction proceeds via a hydrogen autotransfer pathway. This journal is
Efficient Organoruthenium Catalysts for α-Alkylation of Ketones and Amide with Alcohols: Synthesis of Quinolines via Hydrogen Borrowing Strategy and their Mechanistic Studies
Maji, Ankur,Singh, Anshu,Singh, Neetu,Ghosh, Kaushik
, p. 3108 - 3125 (2020/05/18)
A new family of phosphine free organometallic ruthenium(II) catalysts (Ru1–Ru4) supported by bidentate NN Schiff base ligands (L1–L4 where L1=N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazineylidene)methyl) aniline, L2=N,N-diethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazineylidene)methyl)aniline, L3=N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-yl)hydrazineylidene)methyl)- aniline and L4=N,N-diethyl-4-((2-phenyl-2-(pyridin-2-yl)hydrazineylidene)methyl) aniline) was prepared and characterized. These half-sandwich complexes acted as catalysts for C?C bond formation and exhibited excellent performance in the dehydrogenative coupling of ketones and amides. In the synthesis of C–C bonds, alcohols were utilized as the alkylating agent. A broad range of substrates, including sterically hindered ketones and alcohols, were well tolerated under the optimized conditions (TON up to 47000 and TOF up to 11750 h?1). This ruthenium (II) catalysts were also active towards the dehydrogenative cyclization of o-amino benzyl alcohol for the formation of quinolines derivatives. Various polysubstituted quinolines were synthesized in moderate to excellent yields (TON up to 71000 and TOF up to 11830 h?1). Control experiments were carried out and the ruthenium hydride intermediate was characterized to support the reaction mechanism and a probable reaction pathway of dehydrogenative coupling for the C?C bond formation has been proposed.
Bidentate Ru(II)-NC Complexes as Catalysts for α-Alkylation of Unactivated Amides and Esters
Gong, Dawei,Hu, Bowen,Yang, Weiwei,Chen, Dafa
, p. 4841 - 4847 (2019/11/05)
Five Ru(II)-NC complexes were tested as catalysts for α-alkylation of unactivated amides using alcohols as alkylating agents, and complex {(C5H4N)-(C6H4)}RuCl(CO)(PPh3)2 (1) showed the highest activity. With 0.5 mol% catalyst loading, a series of α-alkylated amides were isolated at 80 °C within 6 hours. Furthermore, under similar conditions, complex 1 was also active for α-alkylation of unactivated esters with alcohols, and the reaction time was shortened to 1.5 hours. The catalytic performance of 1 is comparable to the best reported catalyst.
Manganese-catalyzed direct C-C coupling of α-C-H bonds of amides and esters with alcohols: Via hydrogen autotransfer
Rana, Jagannath,Gupta, Virendrakumar,Balaraman, Ekambaram
supporting information, p. 7094 - 7099 (2019/06/06)
Herein we report an efficient manganese-catalyzed C-alkylation of unactivated amides and tert-butyl acetate using alcohols as alkylating agents. This elegant approach exhibits a broad substrate scope providing the C-C coupled products of amides via a hydrogen auto-transfer strategy using aryl, heteroaryl, and aliphatic alcohols.
Ni-Catalyzed Α-Alkylation of Unactivated Amides and Esters with Alcohols by Hydrogen Auto-Transfer Strategy
Midya, Siba P.,Rana, Jagannath,Pitchaimani, Jayaraman,Nandakumar, Avanashiappan,Madhu, Vedichi,Balaraman, Ekambaram
, p. 3911 - 3916 (2018/11/23)
A transition-metal-catalyzed borrowing hydrogen/hydrogen auto-transfer strategy allows the utilization of feedstock alcohols as an alkylating partner, which avoids the formation of stoichiometric salt waste and enables a direct and benign approach for the construction of C-N and C?C bonds. In this study, a nickel-catalyzed α-alkylation of unactivated amides and ester (tert-butyl acetate) is carried out by using primary alcohols under mild conditions. This C?C bond-forming reaction is catalyzed by a new, molecularly defined nickel(II) NNN-pincer complex (0.1–1 mol %) and proceeds through hydrogen auto-transfer, thereby releasing water as the sole byproduct. In addition, N-alkylation of cyclic amides under Ni-catalytic conditions is demonstrated.
Structure-Based Design and Discovery of New M2 Receptor Agonists
Fish, Inbar,St??el, Anne,Eitel, Katrin,Valant, Celine,Albold, Sabine,Huebner, Harald,M?ller, Dorothee,Clark, Mary J.,Sunahara, Roger K.,Christopoulos, Arthur,Shoichet, Brian K.,Gmeiner, Peter
supporting information, p. 9239 - 9250 (2017/11/30)
Muscarinic receptor agonists are characterized by apparently strict restraints on their tertiary or quaternary amine and their distance to an ester or related center. On the basis of the active state crystal structure of the muscarinic M2 receptor in complex with iperoxo, we explored potential agonists that lacked the highly conserved functionalities of previously known ligands. Using structure-guided pharmacophore design followed by docking, we found two agonists (compounds 3 and 17), out of 19 docked and synthesized compounds, that fit the receptor well and were predicted to form a hydrogen-bond conserved among known agonists. Structural optimization led to compound 28, which was 4-fold more potent than its parent 3. Fortified by the discovery of this new scaffold, we sought a broader range of chemotypes by docking 2.2 million fragments, which revealed another three micromolar agonists unrelated either to 28 or known muscarinics. Even pockets as tightly defined and as deeply studied as that of the muscarinic reveal opportunities for the structure-based design and the discovery of new chemotypes.
A highly efficient catalytic α-alkylation of unactivated amides using primary alcohols
Yao, Wubing,Ma, Xiaochen,Guo, Le,Jia, Xiangqing,Hu, Aiguo,Huang, Zheng
supporting information, p. 2919 - 2921 (2016/06/13)
The α-alkylation of unactivated amides with alcohols is described. Using a NCP-type pincer Ir complex as the precatalyst and KOtBu as the base, the reactions of secondary or tertiary acetamides with benzyl or nonbenzyl primary alcohols occur at 80 °C, furnishing the alkylation products in good yields. This method represents a practical and green means of α-alkylation of amides in a relatively mild, efficient, and selective manner with low catalyst loadings (0.5 mol %).
Ruthenium hydride/nitrogen tridentate ligand-catalyzed α-alkylation of acetamides with primary alcohols
Kuwahara, Takashi,Fukuyama, Takahide,Ryu, Ilhyong
, p. 13702 - 13704 (2013/08/23)
The α-alkylation reaction of acetamides with primary alcohols to afford the corresponding amides was accomplished effectively using RuHCl(CO)(PPh3)3 as a catalyst, nitrogen tridentate ligand L1 as an additive, and KOtBu as a base. While the addition of bpy was effective only for benzylic alcohols, L1 affected the alkylation reaction when both benzylic and non-benzylic type alcohols were used.
Iridium-catalyzed selective α-alkylation of unactivated amides with primary alcohols
Guo, Le,Liu, Yinghua,Yao, Wubing,Leng, Xuebing,Huang, Zheng
supporting information, p. 1144 - 1147 (2013/04/10)
The first α-alkylation of unactivated amides with primary alcohols is described. An effective and robust iridium pincer complex has been developed for selective α-alkylation of tertiary and secondary acetamides involving a borrowing hydrogen methodology. The method is compatible with alcohols bearing various functional groups. This presents a convenient and environmentally benign protocol for α-alkylation of amides.
