4129-40-2Relevant articles and documents
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.
Light-Enabled Radical 1,4-Aryl Migration Via a Phospho-Smiles Rearrangement
De Abreu, Maxime,Belmont, Philippe,Brachet, Etienne
, p. 3758 - 3767 (2021/02/01)
Rearrangement reactions in organic chemistry are attractive strategies to build efficiently complex scaffolds, in just one step, from simple starting materials. Among them, aryl migrations are certainly one of the most useful and straightforward rearrangement for building attractive carbon-carbon bonds. Of note, anionic aryl migration reactions have been largely described compared to their radical counterparts. Recently, visible-light catalysis has proven its efficiency to generate such radical rearrangements due to the concomitant loss of a particle (often CO2 or SO2), which is the driving-force of the reaction. Here, we disclose a Smiles-type rearrangement, triggered by a phosphorus-containing unit (arylphosphoramidate), therefore called "phospho-Smiles"rearrangement, allowing a Csp2-Csp2 bond formation thanks to a 1,4-aryl migration reaction. In addition, combining this approach with a radical hydroamination/amination reaction produces an amination/phospho-Smiles cascade particularly attractive, for instance, to investigate the synthesis of the phthalazine core, a scarcely described scaffold of interest for medicinal chemistry projects.
Copper mediated C(sp2)-H amination and hydroxylation of phosphinamides
Sun, Shang-Zheng,Shang, Ming,Xu, Hui,Cheng, Tai-Jin,Li, Ming-Hong,Dai, Hui-Xiong
supporting information, p. 1444 - 1447 (2020/02/11)
Copper mediated C(sp2)-H amination and hydroxylation of arylphosphinic acid are accomplished by adopting phosphinamide as the directing group. This method is distinguished by its wide substrate scope and excellent functional group tolerance, th
Transition Metal-Free Synthesis of α-Aminophosphine Oxides through C(sp3)?P Coupling of 2-Azaallyls
Wang, Jing,Deng, Guogang,Liu, Chunxiang,Chen, Zhuo,Yu, Kaili,Chen, Wen,Zhang, Hongbin,Yang, Xiaodong
supporting information, p. 2268 - 2273 (2020/03/04)
Radical reactions have been widely applied in C?P bond-forming strategies. Most of these strategies require initiators, transition metal catalysts, or organometallic reagents. Herein, a transition metal-free C(sp3)?P bond formation to prepare α
Copper-Catalyzed Oxidative C(sp3)?H/N?H Cross-Coupling of Hydrocarbons with P(O)?NH Compounds: the Accelerating Effect Induced by Carboxylic Acid Coproduct
Lei, Jian,Yang, Yincai,Peng, Lingteng,Wu, Lesong,Peng, Ping,Qiu, Renhua,Chen, Yi,Au, Chak-Tong,Yin, Shuang-Feng
, p. 1689 - 1696 (2019/03/07)
An chelation-assisted oxidative C(sp3)?H/N?H cross coupling of hydrocarbons with P(O)?NH compounds using copper acetate as catalyst is described. The results of kinetic experiments, mechanistic studies and DFT calculations demonstrate the importance of acetic acid coproduct as an additive for promoting the formation of intermediate bis((diphenylphosphoryl)(quinolin-8-yl)amino)copper (6), and consequently accelerating the construction of C(sp3)?N bond. The reaction proceeded efficiently with a wide array of hydrocarbons and P(O)?NH compounds, and the rate acceleration induced by the acetic acid coproduct have been repeatedly proven. Furthermore, the efficiency of small-scale reaction could be retained upon gram-scale synthesis in a continuous manner. (Figure presented.).
Cobalt-Catalyzed Diastereoselective [4+2] Annulation of Phosphinamides with Heterobicyclic Alkenes at Room Temperature
Nallagonda, Rajender,Thrimurtulu, Neetipalli,Volla, Chandra M. R.
supporting information, p. 255 - 260 (2017/11/13)
Cobalt-catalyzed sp2 C?H bond functionalization of diarylphosphinamides with heterobicyclic alkenes was demonstrated at room temperature employing commercially available cobalt(II)-salts. The effectiveness of this strategy was illustrated with the reaction of various 8-aminoquinoline derived phosphinic amides and 7-oxa/azabenzonorbornadienes. The reaction conditions exhibited excellent functional group tolerance and high diastereoselectivities. Furthermore, extension of this approach to the preparation of polyaryl cyclic phosphinamides was achieved through the dehydrative ring opening/aromatization sequence. (Figure presented.).
Chelation-assisted C-N cross-coupling of phosphinamides and aryl boronic acids with copper powder at room temperature
Peng, Yao,Lei, Jian,Qiu, Renhua,Peng, Lingteng,Au, Chak-Tong,Yin, Shuang-Feng
supporting information, p. 4065 - 4070 (2018/06/12)
A protocol for the chelation-assisted C-N cross-coupling of phosphinamides and aryl boronic acids with copper powder under an oxygen atmosphere is reported. This reaction proceeds efficiently to afford fully substituted unsymmetrical N-arylation phosphinamides at room temperature in excellent yields. Diverse unstable functional groups on the benzene ring of aryl boronic acids such as vinyl, formyl, acetyl, sulfonyl, acetylamino, cyano, nitro, and trifluoromethyl can be accommodated.
Direct, oxidative halogenation of diaryl- or dialkylphosphine oxides with (dihaloiodo)arenes
Eljo, Jasmin,Murphy, Graham K.
supporting information, p. 2965 - 2969 (2018/06/30)
The oxidative halogenation of diaryl- or dialkylphosphine oxides with the hypervalent iodine reagents (difluoroiodo)toluene (p-TolIF2, 1) and (dichloroiodo)benzene (PhICl2, 2) is reported. Phosphoric fluorides could be recovered in 32–75% yield, or they could be trapped with EtOH to give the corresponding phosphinate in typically good yield. Phosphoric chlorides were not readily isolable, and were trapped with alcohol and amine nucleophiles, giving diaryl- or dialkylphos-phinates and phosphinamides in up to 90% yield.
Rhodium(III)-Catalyzed Enantiotopic C?H Activation Enables Access to P-Chiral Cyclic Phosphinamides
Sun, Yang,Cramer, Nicolai
supporting information, p. 364 - 367 (2016/12/30)
Compounds with stereogenic phosphorus atoms are frequently used as ligands for transition-metal as well as organocatalysts. A direct catalytic enantioselective method for the synthesis of P-chiral compounds from easily accessible diaryl phosphinamides is presented. The use of rhodium(III) complexes equipped with a suitable atropochiral cyclopentadienyl ligand is shown to enable an enantiodetermining C?H activation step. Upon trapping with alkynes, a broad variety of cyclic phosphinamides with a stereogenic phosphorus(V) atom are formed in high yields and enantioselectivities. Moreover, these can be reduced enantiospecifically to P-chiral phosphorus(III) compounds.
Allenes in asymmetric catalysis: Asymmetric ring opening of meso-epoxides catalyzed by allene-containing phosphine oxides
Pu, Xiaotao,Qi, Xiangbing,Ready, Joseph M.
supporting information; experimental part, p. 10364 - 10365 (2009/12/03)
(Chemical Equation Presented) Unsymmetrically substituted allenes (1,2-dienes) are inherently chiral and can be prepared in optically pure form. Nonetheless, to date the allene framework has not been incorporated into ligands for asymmetric catalysis. Since allenes project functionality differently than either tetrahedral carbon or chiral biaryls, they may create complementary chiral environments. This study demonstrates that optically active, C 2-symmetric allene-containing bisphosphine oxides can catalyze the addition of SiCl4 to meso-epoxides with high enantioselectivity. The epoxide opening likely involves generation of a Lewis acidic, cationic (bisphosphine oxide)SiCl3 complex. The fact that high asymmetric induction is observed suggests that allenes may represent a new platform for the development of ligands and catalysts for asymmetric synthesis.
