105962-56-9Relevant articles and documents
Silver-Promoted Direct Phosphorylation of Bulky C(sp2)-H Bond to Build Fully Substituted β-Phosphonodehydroamino Acids
Cao, Hao-Qiang,Liu, Hao-Nan,Liu, Zhe-Yuan,Qiao, Baokun,Zhang, Fa-Guang,Ma, Jun-An
supporting information, p. 6414 - 6419 (2020/09/02)
A general and practical cross-dehydrogenative coupling protocol between readily available trisubstituted α,β-dehydro α-amino carboxylic esters and H-phosphites is described. This C(sp2)-H phosphorylation reaction proceeds with absolute Z-selectivity promoted by silver salt in a radical relay manner. The bulky tetrasubstituted β-phosphonodehydroamino acids were obtained in grams and added new modules to the toolkit for peptide modifications.
Ni(ii)-Catalyzed vinylic C-H functionalization of 2-acetamido-3-arylacrylates to access isotetronic acids
Das, Eshani,Mal, Dipakranjan,Roy, Avijit,Roy, Biswajit
supporting information, p. 3697 - 3706 (2020/06/03)
A ligand-free Ni(ii)-catalyzed cascade annulation reaction for the synthesis of 4-aryl-substituted isotetronic acids from 2-acetamido-3-arylacrylatesviavinylic C-H functionalization is reported. The reaction proceeds through heteroatom guided electrophilic insertion of nickel to the vinylic double bond followed by annulation with dibromomethane. This unconventional route features cascade steps, sole product formation, multiple functional group tolerance, low cost of catalysts and reagents, and readily available starting materials. Using this method, various aryl-substituted isotetronic acids have been synthesized which are biologically relevant. The annulation of 2-acetamido-3-arylacrylates has also been assessed with 1,2-dichloroethane, which resulted in the rearranged annulated products of 5-methyl substituted isotetronic acids.
An Atropos Chiral Biphenyl Bisphosphine Ligand Bearing Only 2,2′-Substituents and Its Application in Rh-Catalyzed Asymmetric Hydrogenation
Jia, Jia,Ling, Zheng,Zhang, Zhenfeng,Tamura, Ken,Gridnev, Ilya D.,Imamoto, Tsuneo,Zhang, Wanbin
supporting information, p. 738 - 743 (2017/12/26)
An atropos chiral biphenyl bisphosphine ligand bearing only 2,2′-substituents was rationally designed and easily synthesized utilizing a bulky chiral t-butylmethylphosphino block. Computational results showed a large difference in the free energies betwee
Temperature-controlled bidirectional enantioselectivity in a dynamic catalyst for asymmetric hydrogenation
Storch, Golo,Trapp, Oliver
supporting information, p. 3580 - 3586 (2015/03/18)
Asymmetric catalysis using enantiomerically pure catalysts is one of the most widely used methods for the preparation of enantiomerically pure compounds. The separate synthesis of both enantiomerically pure compounds requires tedious and time-consuming pr
Cation-triggered switchable asymmetric catalysis with chiral aza-crownphos
Ouyang, Guang-Hui,He, Yan-Mei,Li, Yong,Xiang, Jun-Feng,Fan, Qing-Hua
supporting information, p. 4334 - 4337 (2015/04/14)
An aza-crown ether, modified phosphoramidite ligand, has been designed and synthesized. The ON/OFF reversible switch of catalytic activity for its rhodium catalyst was thoroughly investigated in the asymmetric hydrogenation of dehydroamino acid esters modulated by host-guest interactions. In the OFF state, the catalyst is almost inactive (less than 1% conversion) because of the formation of an intermolecular sandwich complex by two aza-crown ether moities and the cationic rhodium metal center. In using alkali-metal-cations as the trigger, the catalytic activity was turned ON and consequently resulted in full conversions and excellent enantioselectivities (up to 98% ee).
Synthesis of oxazoles from enamides via phenyliodine diacetate-mediated intramolecular oxidative cyclization
Zheng, Yunhui,Li, Xuming,Ren, Chengfeng,Zhang-Negrerie, Daisy,Du, Yunfei,Zhao, Kang
, p. 10353 - 10361 (2013/01/15)
A group of functionalized oxazoles were synthesized in moderate to good yields from enamides via phenyliodine diacetate (PIDA)-mediated intramolecular cyclization. The main advantageous features of the present method include its broad substrate scope and the heavy-metal-free characteristic of the oxidative carbon-oxygen bond formation process.
Ligand-free palladium catalysed Heck reaction of methyl 2-acetamido acrylate and aryl bromides as key step in the synthesis of enantiopure substituted phenylalanines
Willans, Charlotte E.,Mulders, Jan M.C.A.,de Vries, Johannes G.,de Vries, André H.M.
, p. 494 - 497 (2007/10/03)
A range of substituted aryl bromides were coupled with methyl 2-acetamido acrylate using ligand-free palladium catalysis. Subsequently asymmetric hydrogenation with Rh/MonoPhos yielded substituted phenylalanines in high enantioselectivities (e.e. 92-99%).
β-aryl and β-vinyl-αβ-didehydro-α-aminoacid derivatives through the palladium-catalysed reaction of aryl and vinyl triflates with methyl α-acetamidoacrylate
Arcadi,Cacchi,Marinelli,Morera,Ortar
, p. 7151 - 7164 (2007/10/02)
Vinyl and aryl triflates react with methyl α-acetamidoacrylate in the presence of catalytic amounts of palladium to give β-vinyl and β-aryl-αβ-didehydro-α-aminoacid derivatives in good to high yields. A variety of reaction conditions were examined. Vinyl
