25726-04-9Relevant articles and documents
A Cooperative Ternary Catalysis System for Asymmetric Lactonizations of α-Ketoesters
Murauski, Kathleen J. R.,Walden, Daniel M.,Cheong, Paul Ha-Yeon,Scheidt, Karl A.
, p. 3713 - 3719 (2017)
A general and enantioselective N-heterocyclic carbene (NHC)-catalyzed lactonization of simple enals and α-ketoesters has been discovered using a new ternary cooperative catalytic system. The highly selective annulation was achieved by using a combination of a chiral NHC, a hydrogen-bond donor, and a metal salt, facilitating self-assembly of the reactive partners. A proposed model for this new mode of NHC chiral relay catalysis is supported by experimental and computational mechanistic studies. (Figure presented.).
Crystallization-induced diastereomer transformation of thiohydantoin derivatives
Mino, Takashi,Sakamoto, Masami,Uemura, Naohiro,Yoshida, Yasushi
, (2020)
Crystallization-induced diastereomer transformation of valuable thiohydantoin derivatives was developed for the first time. Three thiohydantoins synthesized from three (R)-N-phenethylthioureas and benzoylformyl chloride were obtained as diasteromeric mixt
A photo-auxiliary approach - enabling excited state classical phototransformations with metal free visible light irradiation
Iyer, Akila,Jockusch, Steffen,Sivaguru, Jayaraman
, p. 1692 - 1695 (2017)
Most traditional photoreactions require UV light to yield the desired product. To address this issue, photoreaction of hydrazide based chromophores was evaluated with visible light using a metal free photocatalyst to afford photoproducts in high yields. This hydrazide functionality itself may be removed/modified after the photoreaction, highlighting its role as a “photo-auxiliary”. A preliminary mechanistic model based on photophysical experiments is provided to highlight the generality of the strategy.
Non-Bonding 1,4-Sulphur-Oxygen Interaction Governs the Reactivity of α-Ketothioesters in Triphenylphosphine-Catalyzed Cyclization with Acetylenedicarboxylates
Bankura, Abhijit,Saha, Jayanta,Maity, Rajib,Das, Indrajit
supporting information, p. 1014 - 1021 (2020/12/31)
α-Ketothioesters undergo triphenylphosphine (PPh3)-catalyzed cyclization with acetylenedicarboxylate esters smoothly, in contrast to α-ketooxoesters which require more drastic conditions with the limited substrate scope. The reaction works well
Synthesis of N-trifluoromethyl amides from carboxylic acids
Flavell, Robert R.,Liu, Jianbo,Parker, Matthew F. L.,Toste, F. Dean,Wang, Sinan,Wilson, David M.
supporting information, p. 2245 - 2255 (2021/08/12)
Found in biomolecules, pharmaceuticals, and agrochemicals, amide-containing molecules are ubiquitous in nature, and their derivatization represents a significant methodological goal in fluorine chemistry. Trifluoromethyl amides have emerged as important functional groups frequently found in pharmaceutical compounds. To date, there is no strategy for synthesizing N-trifluoromethyl amides from abundant organic carboxylic acid derivatives, which are ideal starting materials in amide synthesis. Here, we report the synthesis of N-trifluoromethyl amides from carboxylic acid halides and esters under mild conditions via isothiocyanates in the presence of silver fluoride at room temperature. Through this strategy, isothiocyanates are desulfurized with AgF, and then the formed derivative is acylated to afford N-trifluoromethyl amides, including previously inaccessible structures. This method shows broad scope, provides a platform for rapidly generating N-trifluoromethyl amides by virtue of the diversity and availability of both reaction partners, and should find application in the modification of advanced intermediates.
