94940-35-9Relevant academic research and scientific papers
Electrochemical Oxidative C–H Phosphonylation of thiazole derivatives in ambient conditions
Li, Yang,Wu, Lei,Yang, Yan-Tong,Zhu, Jie,Zhu, Peng-Wei
, (2021/12/07)
We herein report a direct electrochemical dehydrogenative C–H phosphonylation of thiazoles derivatives with H2 evolution. Employing electricity as the green and sole oxidant, cheap metal as electrode, the anodic oxidation together with cathodic hydrogen evolution process provides a green and efficient strategy for C–H phosphonylation. A diverse range of phosphorus products were constructed under external metal and oxidant-free conditions at ambient temperature, featuring atom economy, simple operation and wide reaction scope.
Microwave-Assisted Ruthenium- and Rhodium-Catalyzed Couplings of α-Amino Acid Ester-Derived Phosphinamides with Alkynes
Li, Xue-Hong,Gong, Jun-Fang,Song, Mao-Ping
supporting information, (2021/12/23)
Two different types of new phosphinamide α-amino ester derivatives have been prepared in moderate to high yields via ruthenium(II) and rhodium(III)-catalyzed ortho-C?H functionalization under microwave irradiation. Specifically, the ortho-alkenylated phosphinamides were produced through coupling of phosphinamides containing an α-substituted or α,α-disubstituted α-amino ester with internal alkynes under ruthenium catalysis. In contrast, Ru and the more effective Rh-catalyzed coupling of the α-unsubstituted glycine ester phosphinamide with alkynes resulted in formation of oxidative annulation products, phosphaisoquinolin-1-ones. The developed methods feature the use of easily accessible starting materials, short reaction time, exclusive E-stereoselectivity (for ortho-alkenylation) and good functional group tolerance. The alkenylation reaction was readily scaled up to gram scale. Furthermore, the obtained alkenylated phosphinamide could be transformed into P-containing dipeptides through hydrolysis of the ester group in the catalysis product and subsequent condensation with an α-amino ester.
B(C6F5)3-catalyzed O-H insertion reactions of diazoalkanes with phosphinic acids
Jiang, Jun,Zhang, Xinzhi,Zhang, Yangyang,Zhao, Jincheng
supporting information, p. 5772 - 5776 (2021/07/12)
A highly efficient base-, metal-, and oxidant-free catalytic O-H insertion reaction of diazoalkanes and phosphinic acids in the presence of B(C6F5)3has been developed. This powerful methodology provides a green approach towards the synthesis of a broad spectrum of α-phosphoryloxy carbonyl compounds with good to excellent yields (up to 99% yield). The protocol features the advantages of operational simplicity, high atom economy, practicality, easy scalability and environmental friendliness.
Organic photoredox catalytic α-C(sp3)-H phosphorylation of saturated: Aza -heterocycles
Yi, Ming-Jun,Xiao, Teng-Fei,Li, Wen-Hui,Zhang, Yi-Fan,Yan, Pen-Ji,Zhang, Baoxin,Xu, Peng-Fei,Xu, Guo-Qiang
supporting information, p. 13158 - 13161 (2021/12/16)
A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Br?nsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.
Development of effective bidentate diphosphine ligands of ruthenium catalysts toward practical hydrogenation of carboxylic acids
Saito, Susumu,Wen, Ke,Yoshioka, Shota
supporting information, p. 1510 - 1524 (2021/06/18)
Hydrogenation of carboxylic acids (CAs) to alcohols represents one of the most ideal reduction methods for utilizing abundant CAs as alternative carbon and energy sources. However, systematic studies on the effects of metal-to-ligand relationships on the catalytic activity of metal complex catalysts are scarce. We previously demonstrated a rational methodology for CA hydrogenation, in which CA-derived cationic metal carboxylate [(PP)M(OCOR)]+ (M = Ru and Re; P = one P coordination) served as the catalyst prototype for CA self-induced CA hydrogenation. Herein, we report systematic trial- and-error studies on how we could achieve higher catalytic activity by modifying the structure of bidentate diphosphine (PP) ligands of molecular Ru catalysts. Carbon chains connecting two P atoms as well as Ar groups substituted on the P atoms of PP ligands were intensively varied, and the induction of active Ru catalysts from precatalyst Ru(acac)3 was surveyed extensively. As a result, the activity and durability of the (PP)Ru catalyst substantially increased compared to those of other molecular Ru catalyst systems, including our original Ru catalysts. The results validate our approach for improving the catalyst performance, which would benefit further advancement of CA self-induced CA hydrogenation.
Enantiodivergent Kinetic Resolution of 1,1′-Biaryl-2,2′-Diols and Amino Alcohols by Dipeptide-Phosphonium Salt Catalysis Inspired by the Atherton–Todd Reaction
Chen, Yuan,Fang, Siqiang,Pan, Jianke,Ren, Xiaoyu,Tan, Jian-Ping,Wang, Tianli,Zhang, Hongkui
supporting information, p. 14921 - 14930 (2021/05/10)
A highly enantiodivergent organocatalytic method is disclosed for the synthesis of atropisomeric biaryls via kinetic resolution inspired by a dipeptide-phosphonium salt-catalyzed Atherton–Todd (A-T) reaction. This flexible approach led to both R- and S-enantiomers by fine-tuning of bifunctional phosphonium with excellent selectivity factors (s) of up to 1057 and 525, respectively. The potential of newly synthesized O-phosphorylated biaryl diols was illustrated by the synthesis of axially chiral organophosphorus compounds. Mechanistic investigations suggest that the bifunctional phosphonium halide catalyst differentiates between the in-situ-generated P-species in the A-T process, mainly involving phosphoryl chloride and phosphoric anhydride, thus leading to highly enantiodivergent O-phosphorylation reactions. Furthermore hydrogen bonding interactions between the catalysts and phosphorus molecules were crucial in asymmetric induction.
Highly Enantioselective Synthesis of Phosphorus-Containing ?-Benzosultams by Bifunctional Phosphonium Salt-Promoted Hydrophosphonylation
Zhang, Song,Feng, Zhenghuai,Jiang, Chunhui,Yu, Xiaojun,Pan, Jianke,Du, Juan,Jiang, Zhiyu,Chen, Yuan,Wang, Tianli
supporting information, p. 11285 - 11290 (2021/07/02)
?-Benzosultam derivatives are potential drug candidates with diverse biological activities. A series of chiral ?-benzosultams bearing phosphorus functionalities was synthesized by catalytic asymmetric hydrophosphonylation in the presence of a bifunctional phosphonium salt catalyst. The desired hydrophosphonylation products were obtained in good yields with high enantioselectivities, and scale-up reactions and further derivations were successfully accomplished. Some control experiments were also conducted to elucidate the plausible reaction mechanism of this chemical transformation.
Twofold C?H Activation-Based Enantio- and Diastereoselective C?H Arylation Using Diarylacetylenes as Rare Arylating Reagents
Hu, Panjie,Kong, Lingheng,Li, Xingwei,Wang, Fen,Zhu, Xiaolin
supporting information, p. 20424 - 20429 (2021/08/09)
C?H bond activation has been established as an attractive strategy to access axially chiral biaryls, and the most straightforward method is direct C?H arylation of arenes. However, the arylating source has been limited to several classes of reactive and bulky reagents. Reported herein is rhodium-catalyzed 1:2 coupling of diarylphosphinic amides and diarylacetylenes for enantio- and diastereoselective construction of biaryls with both central and axial chirality. This twofold C?H activation reaction stays contrast to the previously explored Miura–Satoh type 1:2 coupling of arenes and alkynes in terms of chemoselectivity and proceeded under mild conditions with the alkyne acting as a rare arylating reagent. Both C?H activation events are stereo-determining and are under catalyst control, with the 2nd C?H activation being diastereo-determining in a remote fashion. Analysis of the stereochemistry of the major and side products suggests moderate enantioselectivity of the initial C?H activation–desymmetrization process. However, the minor (R) rhodium vinyl intermediate is consumed more readily in undesired protonolysis, eventually resulting in high enantio- and diastereoselectivity of the major product.
Metal-free synthesis of phosphinoylchroman-4-ones via a radical phosphinoylation–cyclization cascade mediated by K2S2O8
Liu, Qiang,Lu, Weibang,Wang, Xiaoxia,Xie, Guanqun
supporting information, p. 1974 - 1982 (2020/10/02)
A variety of chroman-4-ones bearing phosphine oxide motifs were conveniently synthesized from readily available diphenylphosphine oxides and alkenyl aldehydes via a metal-free tandem phosphinoylation/cyclization protocol. The reaction utilizes K2S2O8 as oxidant and proceeds in DMSO/H2O at environmentally benign conditions with a broad substrate scope and afforded the title compounds in moderate yields.
Cobaloxime Catalysis for Enamine Phosphorylation with Hydrogen Evolution
Lei, Tao,Liang, Ge,Cheng, Yuan-Yuan,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
supporting information, p. 5385 - 5389 (2020/07/08)
Direct phosphorylation of enamine and enamide with hydrogen evolution was realized via cobaloxime catalysis under visible-light irradiation. Control experiments and spectroscopic studies demonstrated a reductive quenching pathway of cobaloxime catalyst to produce phosphinoyl radical, which underwent cross-coupling with various enamines (and enamides) to give diverse β-phosphinoyl products in good to excellent yields. More interestingly, Z/E mixture of acyclic enamines could convert into single Z-products with good reactivity.
