72763-87-2Relevant academic research and scientific papers
π-Coordinating Chiral Primary Amine/Palladium Synergistic Catalysis for Asymmetric Allylic Alkylation
Chai, Junli,Luo, Sanzhong,Mi, Xueling,Wang, Yaning,You, Chang,Zhang, Jie,Zhang, Long
supporting information, p. 3184 - 3195 (2020/03/11)
We report an arene-containing chiral primary amine as a dual aminocatalyst and ligand: The π-coordinating aminocatalyst/palladium synergistic catalysis for asymmetric allylic alkylation of α-branched β-ketocarbonyls. The use of arene-containing chiral primary amine catalyst led to not only enhanced reaction rate but also reversed chiral induction compared with its sterically bulky derivative. Both enantiomers of the allylic adducts bearing acyclic all-carbon quaternary stereocenters could be obtained from the same configured chiral aminocatalysts with high efficiency and excellent regio-, stereo-, and enantioselectivity. Mechanistic studies revealed a distinctive Pd-arene π-coordination mode for effective catalysis. The π-coordinating chiral primary amine catalyst could be successfully applied in the asymmetric allylation reactions of vinylethylene carbonates, vinyl epoxides, or simple allylic alcohols.
Chiral phosphine ligand libraries based on the Bull–James three-component supramolecular assembly
Su, Hsin Y.,Gorelik, Daniel,Taylor, Mark S.
, p. 190 - 202 (2019/01/14)
An approach to the synthesis of libraries of chiral phosphine ligands is described, using condensations of 2-formylarylboronic acids, diols or related compounds, and aminophosphines. The three-component nature of this condensation, along with the ready av
Enantioselective Palladium-Catalyzed Decarboxylative Allylation of β-Keto Esters Assisted by a Thiourea
Qian, Hua,Gu, Guoxian,Zhou, Qinghai,Lu, Jiaxiang,Chung, Lung Wa,Zhang, Xumu
, p. 51 - 56 (2017/10/06)
Enantioselective intramolecular decarboxylative allylation of β-keto esters catalyzed by a palladium bis(phosphine)-thiourea complex is reported. This procedure is not only effective for β-keto esters, but also effective for β-keto amides. An intermolecular variant of the asymmetric decarboxylative allylation is also established. DFT calculations indicate that an outer-sphere mechanism is viable for the decarboxylative allylation of β-keto esters.
Asymmetric Allylation of 2-Oxocycloalkanecarboxylates
Yoshida, Masanori,Yano, Shohei,Hara, Shoji
, p. 1295 - 1300 (2017/03/11)
In this study, the highly enantioselective α-allylation of α-substituted β-ketoesters, particularly 2-oxocycloalkanecarboxylates, is achieved by synergistic catalysis with an achiral palladium complex and a chiral primary amino acid. Various α-allylated β-ketoesters containing a quaternary carbon stereogenic center are synthesized in high yields (up to 97%) with excellent enantioselectivity (up to 99% ee).
Asymmetric α-Allylation of α-Substituted β-Ketoesters with Allyl Alcohols
Yoshida, Masanori
, p. 12821 - 12826 (2017/12/08)
Enantioselective α-allylation of α-substituted β-ketoesters with simple allyl alcohols was successfully performed by synergistic catalysis with the catalyst combination of a chiral primary amino acid and an achiral palladium complex without additional promotors like acids or bases. The allylation reaction and generation of a chiral quaternary carbon stereocenter proceeded smoothly to produce α,α-disubstituted β-ketoesters in high yields (91-99%) with high enantioselectivities (90-99% ee).
Catalytic enantioselective claisen rearrangements of O-allyl β-ketoesters
Uyeda, Christopher,Roetheli, Andreas R.,Jacobsen, Eric N.
supporting information; experimental part, p. 9753 - 9756 (2011/02/23)
A chiral guanidinium ion is shown to catalyze enantioselective Claisen rearrangements of O-allyl β-ketoesters in 78-87 % ee (see scheme). The pericyclic nature of the process allows products containing vicinal stereogenic centers to be accessed with both enantio- and diastereocontrol. Copyright
High-throughput screening of the asymmetric decarboxylative alkylation reaction of enolate-stabilized enol carbonates
McDougal, Nolan T.,Virgil, Scott C.,Stoltz, Brian M.
experimental part, p. 1712 - 1716 (2010/08/23)
The use of high-throughput screening allowed for the optimization of reaction conditions for the palladium-catalyzed asymmetric decarboxylative alkylation reaction of enolate-stabilized enol carbonates. Changing to a nonpolar reaction solvent and to an electron-deficient PHOX derivative as ligand from our standard reaction conditions improved the enantioselectivity for the alkylation of a ketal-protected,1,3-diketone-derived enol carbonate from 28% ee to 84% ee. Similar improvements in enantioselectivity were seen for a β-keto ester derived and an α-phenyl cyclohexanone-derived enol carbonate. Georg Thieme Verlag Stuttgart New York.
Synthesis of enantiomerically pure bicyclic lactams
Diedrichs, Nicole,Westermann, Bernhard
, p. 1127 - 1129 (2007/10/03)
Enantiomerically pure homologous 1-azabicyclo-[x.y.0]alkanones (x = 4-5, y = 4-7) can be synthesized by ring closing olefin metathesis using Grubbs' ruthenium catalyst. By starting from monocyclic lactams, the bicyclic products, even eight- and nine-membered rings, are formed in high yields. The monocyclic lactames can be obtained enantiomerically pure by enzyme-catalyzed kinetic resolution.
Enantioselective synthesis of spiro [4.4]non- and spiro[4.5]dec-2-ene-1,6-diones
Chitkul,Pinyopronpanich,Thebtaranonth,Thebtaranonth,Taylor
, p. 1099 - 1102 (2007/10/02)
Spiro[4.4]non- and spiro[4.5]dec-2-ene-1,6-diones [2; N = 0 and 1] were prepared in moderate to high enantiomeric purities via asymmetric allylation of enamines 6 and ketal derivatives 7 and 8 formed from keto-esters 5, followed by a carbanionic cyclization process.
