648928-83-0Relevant academic research and scientific papers
A donor-acceptor complex enables the synthesis of: E -olefins from alcohols, amines and carboxylic acids
Chen, Kun-Quan,Shen, Jie,Wang, Zhi-Xiang,Chen, Xiang-Yu
, p. 6684 - 6690 (2021/05/31)
Olefins are prevalent substrates and functionalities. The synthesis of olefins from readily available starting materials such as alcohols, amines and carboxylic acids is of great significance to address the sustainability concerns in organic synthesis. Metallaphotoredox-catalyzed defunctionalizations were reported to achieve such transformations under mild conditions. However, all these valuable strategies require a transition metal catalyst, a ligand or an expensive photocatalyst, with the challenges of controlling the region- and stereoselectivities remaining. Herein, we present a fundamentally distinct strategy enabled by electron donor-acceptor (EDA) complexes, for the selective synthesis of olefins from these simple and easily available starting materials. The conversions took place via photoactivation of the EDA complexes of the activated substrates with alkali salts, followed by hydrogen atom elimination from in situ generated alkyl radicals. This method is operationally simple and straightforward and free of photocatalysts and transition-metals, and shows high regio- and stereoselectivities.
Synthesis of protected α-amino acids: Via decarboxylation amination from malonate derivatives
Dai, Qipu,Fu, Hui,Hu, Changwen,Li, Peihe,Li, Xiaoying,Wang, Zheng
, p. 4439 - 4446 (2020/10/20)
A general and efficient strategy for the synthesis of protected α-amino acids is reported. The method uses malonate derivatives as the starting materials and Cs2CO3 as a base at 60 degrees, giving α-amino acid derivatives in moderate yields by releasing CO2. This methodology shows broad substrate scope (primary and secondary acids), excellent functional group tolerance and high efficiency to give the desired products under mild reaction conditions. It also allows the construction of β and γ-amino acids and other unnatural products.
A process for the preparation and synthetic ChondriamideA and ChondriamideC method (by machine translation)
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Paragraph 0093-0097; 0227-0230, (2018/09/13)
The invention provides a process for the preparation of synthetic Chondriamide A and Chondriamide C and method, wherein the invention provides a process for the preparation, including: formula (I) compounds of structure, palladium catalyst, phosphorus ligand, alkali and organic solvent at room temperature the illumination reaction, formula (II) structure obtained olefin; wherein through the selection of a particular phosphorus ligand; make the method of the invention can be under the photocatalysis, room temperature to realize high-efficient catalytic conversion, and the mild reaction conditions, simple operation, in line with the development of green environment-friendly chemical requirements, and the range of choice of substrate and functional group compatibility has more universal, and has outstanding chemical selectivity; and the method can be successfully applied to complex molecular introducing carbon-carbon double bond to the programme, to optimize a part of the drug molecular synthesis strategy, improve the synthesis efficiency, reduce the cost, with industrial synthetic value and prospects. (by machine translation)
Decarboxylative Elimination of N-Acyl Amino Acids via Photoredox/Cobalt Dual Catalysis
Cartwright, Kaitie C.,Tunge, Jon A.
, p. 11801 - 11806 (2018/12/11)
A dual-catalytic strategy for the synthesis of enamides and enecarbamates directly from easily accessible and inexpensive amino acids has been realized. This mild and efficient protocol makes use of an organic photoredox catalyst and a cobaloxime catalyst to achieve decarboxylative elimination using hydrogen evolution to drive the oxidation. Thus, the reaction occurs without a stoichiometric oxidant or the forcing conditions previously employed in attempts to achieve similar eliminations.
Chiral phosphoric acid catalyzed enantioselective annulation of acyclic enecarbamates to: In situ -generated ortho -quinone methides
Gharui, Chandan,Singh, Shreya,Pan, Subhas Chandra
supporting information, p. 7272 - 7276 (2017/09/25)
The first organocatalytic asymmetric reaction of acyclic enecarbamates with o-quinone methides is disclosed. BINOL-based phosphoric acid catalysts were found to be suitable for the annulation reaction. With 10 mol% of the TRIP catalyst, high yields as well as excellent diastereo- and enantioselectivities are achieved for a variety of 2,3,4-trisubstituted chroman products.
Palladium-Catalyzed Decarboxylative Synthesis of Arylamines
Dai, Qipu,Li, Peihe,Ma, Nuannuan,Hu, Changwen
supporting information, p. 5560 - 5563 (2016/11/17)
A novel approach has been developed for the synthesis of arylamines via the palladium-catalyzed intramolecular decarboxylative coupling (IDC) of aroyloxycarbamates, obtained in situ by reacting aryl carboxylic acids with hydroxycarbamates. The reaction offers facile access to structurally diverse arylamines with the site-specific formation of the C(sp2)-N bond under mild conditions.
Decarbonylative approach to the synthesis of enamides from amino acids: Stereoselective synthesis of the (Z)-aminovinyl-d-cysteine unit of mersacidin
Garcia-Reynaga, Pablo,Carrillo, Angela K.,Vannieuwenhze, Michael S.
supporting information; experimental part, p. 1030 - 1033 (2012/04/04)
The Pd- and Ni-promoted decarbonylation of amino acid thioesters proceeds smoothly to yield enamides. The synthesis of the (S)-(Z)-AviMeCys subunit of mersacidin, an MRSA-active lantibiotic, via this approach, is described.
Enamides accessed from aminothioesters via a Pd(0)-catalyzed decarbonylative/β-hydride elimination sequence
Min, Geanna K.,Hernandez, Dacil,Lindhardt, Anders T.,Skrydstrup, Troels
supporting information; experimental part, p. 4716 - 4719 (2010/12/25)
A facile synthesis of various enamides from aminothioesters via a palladium(0)-catalyzed decarbonylation/β-hydride elimination is reported. This protocol was applied to mercaptopyridyl C-terminal modified peptides for the generation of enamides without ep
Enantioselective Friedel-Crafts reaction of electron-rich alkenes catalyzed by chiral Bronsted acid
Terada, Masahiro,Sorimachi, Keiichi
, p. 292 - 293 (2008/04/18)
We present the first enantioselective catalysis of the Friedel-Crafts reaction via activation of electron-rich multiple bonds by a chiral Bronsted acid. The reaction of various indole derivatives with a broad range of substituted enecarbamates affords the
Preparation and applications of a polymer-supported phosphoryl azide
Lu, Yuhua,Taylor, Richard T.
, p. 9267 - 9269 (2007/10/03)
A polymer-supported diphenylphosphoryl azide was prepared. This polymer-supported version of DPPA is useful due to its lower toxicity, moisture tolerance and ease of workup after reaction. The synthetic application of this solid-phase reagent was explored by conversion of a variety of carboxylic acids to urethanes and ureas through Curtius rearrangement reactions. Carboxylic acids bearing different functional groups (aromatic, aliphatic and heterocyclic carboxylic acids) were subjected to the reaction. The corresponding products were isolated with satisfactory yields.
