456-71-3Relevant academic research and scientific papers
Radical C?H Trifluoromethoxylation of (Hetero)arenes with Bis(trifluoromethyl)peroxide
Dix, Stefan,Golz, Paul,Schmid, Jonas R.,Riedel, Sebastian,Hopkinson, Matthew N.
supporting information, p. 11554 - 11558 (2021/07/09)
Trifluoromethoxylated (hetero)arenes are of great interest for several disciplines, especially in agro- and medicinal chemistry. Radical C?H trifluoromethoxylation of (hetero)arenes represents an attractive approach to prepare such compounds, but the high cost and low atom economy of existing .OCF3 radical sources make them unsuitable for the large-scale synthesis of trifluoromethoxylated building blocks. Herein, we introduce bis(trifluoromethyl)peroxide (BTMP, CF3OOCF3) as a practical and efficient trifluoromethoxylating reagent that is easily accessible from inexpensive bulk chemicals. Using either visible light photoredox or TEMPO catalysis, trifluoromethoxylated arenes could be prepared in good yields under mild conditions directly from unactivated aromatics. Moreover, TEMPO catalysis allowed for the one-step synthesis of valuable pyridine derivatives, which have been previously prepared via multi-step approaches.
Atomically Dispersed Ru on Manganese Oxide Catalyst Boosts Oxidative Cyanation
Gates, Bruce C.,Guan, Erjia,Meng, Xiangju,Wang, Chengtao,Wang, Hai,Wang, Liang,Wang, Sai,Xiao, Feng-Shou,Xu, Dongyang,Xu, Hua,Yang, Bo,Zhang, Jian
, p. 6299 - 6308 (2020/07/21)
There is a strong incentive for environmentally benign and sustainable production of organic nitriles to avoid the use of toxic cyanides. Here we report that manganese oxide nanorod-supported single-site Ru catalysts are active, selective, and stable for oxidative cyanation of various alcohols to give the corresponding nitriles with molecular oxygen and ammonia as the reactants. The very low amount of Ru (0.1 wt %) with atomic dispersion boosts the catalytic performance of manganese oxides. Experimental and theoretical results show how the Ru sites enhance the ammonia resistance of the catalyst, bolstering its performance in alcohol dehydrogenation and oxygen activation, the key steps in the oxidative cyanation. This investigation demonstrates the high efficiency of a single-site Ru catalyst for nitrile production.
Base-Mediated Amination of Alcohols Using Amidines
Chen, Jianbin,Fang, Yanchen,Jia, Xiaofei,Jiang, Shaohua,Li, Zehua,Liang, Zuyu,Lu, Fenghong,Qi, Shuo,Ren, Chaoyu,Yu, Shuangming,Zhang, Chunyan,Zhang, Guoying,Zhang, Sheng
, p. 7728 - 7738 (2020/07/15)
Novel and efficient base-mediated N-alkylation and amidation of amidines with alcohols have been developed, which can be carried out in one-pot reaction conditions, which allows for the synthesis of a wide range of N-alkyl amines and free amides in good to excellent yields with high atom economy. In contrast to borrowing hydrogen/hydrogen autotransfer or oxidative-type N-alkylation reactions, in which alcohols are activated by transition-metal-catalyzed or oxidative aerobic dehydrogenation, the use of amidines provides an effective surrogate of amines. This circumvents the inherent necessity in N-alkylation of an oxidant or a catalyst to be stabilized by ligands.
Photocatalytic trifluoromethoxylation of arenes and heteroarenes in continuous-flow
Cendón, Borja,Gulías, Moisés,Ho, Michelle,No?l, Timothy,Nyuchev, Alexander V.,Sambiagio, Carlo,Struijs, Job J. C.,Wan, Ting,Wang, Ying
supporting information, p. 1305 - 1312 (2020/07/10)
The first example of photocatalytic trifluoromethoxylation of arenes and heteroarenes under continuous-flow conditions is described. Application of continuous-flow microreactor technology allowed to reduce the residence time up to 16 times in comparison t
(Ar-tpy)RuII(ACN)3: A Water-Soluble Catalyst for Aldehyde Amidation, Olefin Oxo-Scissoring, and Alkyne Oxygenation
Joarder, Dripta De,Gayen, Subrata,Sarkar, Rajarshi,Bhattacharya, Rajarshi,Roy, Sima,Maiti, Dilip K.
, p. 8468 - 8480 (2019/07/03)
The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)RuII(ACN)3, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displayed excellent catalytic activity for several oxidative organic transformations including late-stage C-H functionalization of aldehydes with NH2OR to valuable primary amides in nonconventional aqueous media with excellent yield. Its diverse catalytic power was established for direct oxo-scissoring of a wide range of alkenes to furnish aldehydes and/or ketones in high yield using a low catalyst loading in the water. Its smart catalytic activity under mild conditions was validated for dioxygenation of alkynes to highly demanding labile synthons, 1,2-diketones, and/or acids. This general and sustainable catalysis was successfully employed on sugar-based substrates to obtain the chiral amides, aldehydes, and labile 1,2-diketones. The catalyst is recovered and reused with a moderate turnover. The proposed mechanistic pathway is supported by isolation of the intermediates and their characterization. This multifaceted sustainable catalysis is a unique tool, especially for late-stage functionalization, to furnish the targeted compounds through frequently used amidation and oxygenation processes in the academia and industry.
Radical Trifluoromethoxylation of Arenes Triggered by a Visible-Light-Mediated N?O Bond Redox Fragmentation
Jelier, Benson J.,Tripet, Pascal F.,Pietrasiak, Ewa,Franzoni, Ivan,Jeschke, Gunnar,Togni, Antonio
supporting information, p. 13784 - 13789 (2018/09/14)
A simple trifluoromethoxylation method enables non-directed functionalization of C?H bonds on a range of substrates, providing access to aryl trifluoromethyl ethers. This light-driven process is distinctly different from conventional procedures and occurs through an OCF3 radical mechanism mediated by a photoredox catalyst, which triggers an N?O bond fragmentation. The pyridinium-based trifluoromethoxylation reagent is bench-stable and provides access to synthetic diversity in lead compounds in an operationally simple manner.
Tandem synthesis of aromatic amides from styrenes in water
Sathe, Pratima A.,Karpe, Aniket S.,Parab, Aniket A.,Parade, Babasao S.,Vadagaonkar, Kamlesh S.,Chaskar, Atul C.
supporting information, p. 2820 - 2823 (2018/06/25)
An expedient one-pot synthesis of aromatic amides has been reported from styrenes in the presence of N-bromosuccinimide and iodine by using aqueous ammonia in water. The reaction proceeds through the formation of α-bromoketone as an intermediate in the pr
Highly Selective Ruthenium-Catalyzed Direct Oxygenation of Amines to Amides
Ray, Ritwika,Hazari, Arijit Singha,Chandra, Shubhadeep,Maiti, Debabrata,Lahiri, Goutam Kumar
supporting information, p. 1067 - 1071 (2018/01/03)
Reports on aerobic oxidation of amines to amides are rare, and those reported suffer from several limitations like poor yield or selectivity and make use of pure oxygen under elevated pressure. Herein, we report a practical and an efficient ruthenium-catalyzed synthetic protocol that enables selective oxidation of a broad range of primary aliphatic, heterocyclic and benzylic amines to their corresponding amides, using readily available reagents and ambient air as the sole oxidant. Secondary amines instead, yield benzamides selectively as the sole product. Mechanistic investigations reveal intermediacy of nitriles, which undergo hydration to afford amide as the final product.
Metal-Free Thermal Activation of Molecular Oxygen Enabled Direct α-CH2-Oxygenation of Free Amines
Ghosh, Santanu,Jana, Chandan K.
, p. 260 - 266 (2018/02/19)
Direct oxidation of α-CH2 group of free amines is hard to achieve due to the higher reactivity of amine moiety. Therefore, oxidation of amines involves the use of sophisticated metallic reagents/catalyst in the presence or absence of hazardous oxidants under sensitive reaction conditions. A novel method for direct C-H oxygenation of aliphatic amines through a metal-free activation of molecular oxygen has been developed. Both activated and unactivated free amines were oxygenated efficiently to provide a wide variety of amides (primary, secondary) and lactams under operationally simple conditions without the aid of metallic reagents and toxic oxidants. The method has been applied to the synthesis of highly functionalized amide-containing medicinal drugs, such as O-Me-alibendol and -buclosamide.
Stable and reusable nanoscale Fe2O3-catalyzed aerobic oxidation process for the selective synthesis of nitriles and primary amides
Murugesan, Kathiravan,Senthamarai, Thirusangumurugan,Sohail, Manzar,Sharif, Muhammad,Kalevaru, Narayana V.,Jagadeesh, Rajenahally V.
supporting information, p. 266 - 273 (2018/01/12)
The sustainable introduction of nitrogen moieties in the form of nitrile or amide groups in functionalized molecules is of fundamental interest because nitrogen-containing motifs are found in a large number of life science molecules, natural products and materials. Hence, the synthesis and functionalization of nitriles and amides from easily available starting materials using cost-effective catalysts and green reagents is highly desired. In this regard, herein we report the nanoscale iron oxide-catalyzed environmentally benign synthesis of nitriles and primary amides from aldehydes and aqueous ammonia in the presence of 1 bar O2 or air. Under mild reaction conditions, this iron-catalyzed aerobic oxidation process proceeds to synthesise functionalized and structurally diverse aromatic, aliphatic and heterocyclic nitriles. Additionally, applying this iron-based protocol, primary amides have also been prepared in a water medium.
