81073-06-5Relevant academic research and scientific papers
Expansion of phosphane treasure box for staudinger peptide ligation
Bajaj, Kiran,Pillai, Girinath G.,Sakhuja, Rajeev,Kumar, Dalip
, p. 12147 - 12159 (2020)
A smooth traceless ligation strategy using an airstable phosphane probe (2-(diphenylphosphanyl)phenyl)methanol as a C-terminus activator has been demonstrated at simple and sterically hindered amino acid junctions (Gly, Ala, Trp, Glu). This Staudinger pep
The Trityl-Cation Mediated Phosphine Oxides Reduction
Landais, Yannick,Laye, Claire,Lusseau, Jonathan,Robert, Frédéric
, p. 3035 - 3043 (2021/05/10)
Reduction of phosphine oxides into the corresponding phosphines using PhSiH3 as a reducing agent and Ph3C+[B(C6F5)4]? as an initiator is described. The process is highly efficient, reducing a broad range of secondary and tertiary alkyl and arylphosphines, bearing various functional groups in generally good yields. The reaction is believed to proceed through the generation of a silyl cation, which reaction with the phosphine oxide provides a phosphonium salt, further reduced by the silane to afford the desired phosphine along with siloxanes. (Figure presented.).
Homogeneous Hydrogenation with a Cobalt/Tetraphosphine Catalyst: A Superior Hydride Donor for Polar Double Bonds and N-Heteroarenes
Duan, Ya-Nan,Du, Xiaoyong,Cui, Zhikai,Zeng, Yiqun,Liu, Yufeng,Yang, Tilong,Wen, Jialin,Zhang, Xumu
supporting information, p. 20424 - 20433 (2019/12/27)
The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex-catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24 000 TON and 12 000 h-1 TOF) and excellent chemoselectivities with various aldehydes, ketones, imines, and even N-heteroarenes. The preference for 1,2-reduction over 1,4-reduction makes this method an efficient way to prepare allylic alcohols and amines. Meanwhile, efficient hydrogenation of the challenging N-heteroarenes is also furnished with excellent functional group tolerance. Mechanistic studies and control experiments demonstrated that a CoIH complex functions as a strong hydride donor in the catalytic cycle. Each cobalt intermediate on the catalytic cycle was characterized, and a plausible outer-sphere mechanism was proposed. Noteworthy, external inorganic base plays multiple roles in this reaction and functions in almost every step of the catalytic cycle.
Phosphinoyl-aziridines as a new class of chiral catalysts for enantioselective Michael addition
Wujkowska, Zuzanna,Zawisza, Anna,Le?niak, Stanis?aw,Rachwalski, Micha?
, p. 230 - 235 (2018/12/05)
A series of new optically pure phosphine oxides containing chiral aziridine subunit were synthesized in good yields and applied as organocatalysts in asymmetric Michael reaction of various aliphatic aldehydes with β-nitrostyrene. The corresponding organoc
Cyclic α-Alkoxyphosphonium Salts from (2-(Diphenylphosphino)phenyl)methanol and Aldehydes and Their Application in Synthesis of Vinyl Ethers and Ketones via Wittig Olefination
Huang, Wenhua,Rong, Hong-Ying,Xu, Jie
, p. 6628 - 6638 (2015/10/06)
Cyclic α-alkoxyphosphonium salts have been synthesized from (2-(diphenylphosphino)phenyl)methanol and aldehydes in 36-89% yields. These phosphonium salts are bench-stable solids and undergo Wittig olefination with aldehydes under basic conditions (K2CO3 or t-BuOK) to form benzylic vinyl ethers, which are readily hydrolyzed to 1,2-disubstituted ethanones under acidic conditions. The formation mechanism of these phosphonium salts via hemiacetal is also proposed.
A mild and efficient flow procedure for the transfer hydrogenation of ketones and aldehydes using hydrous zirconia
Battilocchio, Claudio,Hawkins, Joel M.,Ley, Steven V.
supporting information, p. 2278 - 2281 (2013/06/05)
A flow chemistry Meerwein-Ponndorf-Verley (MPV) reduction procedure using partially hydrated zirconium oxide via a machine-assisted approach is reported. The heterogeneous reductive system could be applied to a wide range of functionalized substrates, allowing clean and fast delivery of the alcohol products within a few minutes (6-75 min). In three examples the system was scaled to deliver 50 mmol of product.
First P,P bidentate phosphine-phosphite-type ligand with a Pstereocenter in the phosphite moiety: Synthesis and application in the Pd-catalyzed asymmetric allylic alkylation
Gavrilov,Zheglov,Shiryaev,Potapova,Gavrilov,Volov,Zamilatskov
, p. 1097 - 1102 (2014/03/21)
A new P,P bidentate phosphine-diamidophosphite bearing an asymmetric phosphorus atom in the 1,3,2-diazaphospholidine ring was obtained. A possibility of its application in the palladium-catalyzed enantioselective allylic substitution was demonstrated. A 70% ee was reached in the alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate.
Discovery of a robust and efficient homogeneous silver(I) catalyst for the cycloaddition of azides onto terminal alkynes
McNulty, James,Keskar, Kunal
, p. 5462 - 5470 (2012/10/30)
A highly efficient, chemically stable, and well-defined homogeneous silver(I) catalyst is reported for the cycloaddition of azides onto terminal alkynes (Ag-AAC reaction). The Ag-AAC reaction occurs at room temperature or with heating to deliver exclusive
Stereoselective Wittig olefination reactions employing a novel ortho-P-aryl alkoxide effect
McNulty, James,Keskar, Kunal
scheme or table, p. 7054 - 7057 (2009/04/07)
Non-stabilized ortho-P-alkoxy-substituted ylides react with aromatic and aliphatic aldehydes providing (E)-olefins with high stereocontrol, also allowing easy phosphine oxide removal in certain cases.
Water soluble phosphines Part XV. Syntheses of multiply functionalized and chiral phospine ligands by Pd-catalyzed P-C and C-C coupling reactions
Brauer, David J.,Hingst, Martin,Kottsieper, Konstantin W.,Liek, Christian,Nickel, Thomas,Tepper, Michael,Stelzer, Othmar,Sheldrick, William S.
, p. 14 - 26 (2007/10/03)
Phosphine ligands containing mono- and multiply substituted aromatic substituents (1-13, 19a and 19b) are accessible in high yields by palladium-catalyzed P-C coupling reactions between primary, secondary or disecondary phosphines and iodo- or bromoaromatic compounds. The reaction is of broad applicability and compatible with electron donor or electron acceptor substituents in ortho, meta or para position to the halogen in the aromatic ring systems. It may be performed in protic and aprotic solvents. The chiral spirocyclic boronato complex 15a is formed upon reaction of 3 with boric acid, while with benzeneboronic acid 15c with a peripheral Lewis acid group is obtained. The Pd-mediated P-C coupling reaction of primary phosphines proceeds stepwise, tailor-made chiral secondary (16) and tertiary phosphines (17) being formed in high yield. Through combination with Suzuki-type C-C coupling reactions, the scope of Pd-catalyzed P-C coupling may be extended further, novel ligands (20a, 20b, 21a, 21b) with biphenylyl substituents being accessible. The X-ray structures of the salicylic acid derivative 3 (space group P1) and of ortho-iso-propylphenyl-diphenylphosphine 6 (space group Pbca) have been determined.
