63888-22-2Relevant academic research and scientific papers
Amide/Ester Cross-Coupling via C-N/C-H Bond Cleavage: Synthesis of β-Ketoesters
Chen, Jiajia,Joseph, Devaneyan,Xia, Yuanzhi,Lee, Sunwoo
, p. 5943 - 5953 (2021/04/02)
Activated primary, secondary, and tertiary amides were coupled with enolizable esters in the presence of LiHMDS to obtain good yields of β-ketoesters at room temperature. Notably, this protocol provides an efficient, mild, and high chemoselectivity method
Iridium(III)-Catalyzed C(3)-H Alkylation of Isoquinolines via Metal Carbene Migratory Insertion
Jha, Neha,Singh, Roushan Prakash,Saxena, Paridhi,Kapur, Manmohan
, p. 8694 - 8698 (2021/11/24)
An Ir(III)-catalyzed C(3)-H alkylation of N-acetyl-1,2-dihydroisoquinolines with diverse acceptor-acceptor diazo compounds has been achieved under a single catalytic system via metal carbene migratory insertion. Moreover, further synthetic transformations of the alkylated products such as aromatization, selective decarboxylation, and decarbonylation lead to the formation of several synthetically viable isoquinoline derivatives having immense potentials.
Route exploration and synthesis of the reported pyridone-based PDI inhibitor STK076545
Dockendorff, Chris,Flaumenhaft, Robert,Greve, Eric,Lin, Lin,Lindeman, Sergey V.,Scartelli, Christina
, p. 6665 - 6681 (2020/09/21)
The enzyme protein disulfide isomerase (PDI) is essential for the correct folding of proteins and the activation of certain cell surface receptors, and is a promising target for the treatment of cancer and thrombotic conditions. A previous high-throughput screen identified the commercial compound STK076545 as a promising PDI inhibitor. To confirm its activity and support further biological studies, a resynthesis was pursued of the reported β-keto-amide with an N-alkylated pyridone at the α-position. Numerous conventional approaches were complicated by undesired fragmentations or rearrangements. However, a successful 5-step synthetic route was achieved using an aldol reaction with an α-pyridone allyl ester as a key step. An X-ray crystal structure of the final compound confirmed that the reported structure of STK076545 was achieved, however its lack of PDI activity and inconsistent spectral data suggest that the commercial structure was misassigned.
Mechanochemical electrophilic fluorination of liquid beta-ketoesters
Howard, Joseph L.,Sagatov, Yerbol,Browne, Duncan L.
, p. 3118 - 3123 (2017/12/26)
An improved substrate scope for the mechanochemical electrophilic fluorination of dicarbonyls is reported. The applicable substrates have now been broadened to include liquid β-ketoesters. Key to this capability is the inclusion of a grinding auxiliary (NaCl) to improve mass transfer and prevent pasting or gumming of the reaction mixture. Notably, the use of a small amount of acetonitrile is critical to increasing the rate of reaction, ensuring complete consumption of starting materials during the short reaction times as well as improving the selectivity for the monofluorinated product in the mill.
Metal-free intermolecular cyclopropanation between alkenes and iodonium ylides mediated by PhI(OAc)2·Bu4NI
Tao, Jason,Estrada, Carl D.,Murphy, Graham K.
supporting information, p. 9004 - 9007 (2017/08/15)
A rapid, mild and metal-free intermolecular cyclopropanation between iodonium ylides and alkene-containing substrates mediated by PhI(OAc)2·Bu4NI is reported. Iodonium ylides of cyclic and acyclic 1,3-dicarbonyls were reacted with a variety of mono-, di-, tri- and tetra-substituted alkenes of various structural types to give 29 cyclopropanes in up to 97% yield.
Studies of the Electronic Effects of Zinc Cluster Catalysts and Their Application to the Transesterification of β-Keto Esters
Agura, Kazushi,Hayashi, Yukiko,Wada, Mari,Nakatake, Daiki,Mashima, Kazushi,Ohshima, Takashi
supporting information, p. 1548 - 1554 (2016/06/01)
The electronic effects of tetranuclear zinc cluster catalysts on transesterification were investigated by changing the carboxylate ligands in the clusters. High catalyst activity crucially depended on the balance between Lewis acidity and Br?nsted basicity of the catalyst; this was consistent with the dual activation of both the electrophile and nucleophile by the cooperative zinc centers. In addition, tetranuclear zinc cluster catalysts achieved the transesterification of β-keto esters with unprecedented levels of broad substrate generality, in which a newly developed pentafluoropropionate-bridged zinc cluster and 4-dimethylaminopyridine additive greatly improved the reactivity of sterically congested α- and α,α-disubstituted β-keto esters. Lewis versus Br?nsted: High catalyst activity of zinc clusters on transesterification crucially depend on a balance between Lewis acidity and Br?nsted basicity of the catalyst. Zinc clusters, including a newly developed pentafluoropropionate-bridged zinc cluster, achieved the transesterification of β-keto esters with unprecedented levels of broad substrate generality (see figure).
Primary β-amino acid salt-catalyzed asymmetric Michael addition of benzoylacetates to cyclic enones and its application for the synthesis of enantioenriched 1,5-diketones
Yoshida, Masanori,Kubara, Ami,Hara, Shoji
, p. 180 - 182 (2013/03/28)
The asymmetric Michael addition of benzoylacetates to cyclic enones was successfully carried out by using a primary β-amino acid salt catalyst. The reactions proceeded under mild reaction conditions to produce Michael adducts in high yields and with high enantioselectivities. The obtained Michael adducts were converted into β-benzoylmethylated cyclic ketones by decarboxylation without a significant loss of enantiomeric excess.
Solvent-free Claisen and Cannizzaro reactions
Yoshizawa, Kazuhiro,Toyota, Shinji,Toda, Fumio
, p. 7983 - 7985 (2007/10/03)
Claisen and Cannizzaro reactions were found to proceed efficiently under solvent-free conditions. The solvent-free Claisen reactions were especially effective for the ester substituted with sterically bulky groups, which does not react in solution.
The Reformatsky Reaction of 1-Acyl-3,5-dimethylpyrazoles. A Convenient Preparation of 4-Amino-3-oxoalkanoic Acid Derivatives
Kashima, Choji,Kita, Isanobu,Takahashi, Katsumi,Hosomi, Akira
, p. 723 - 726 (2007/10/02)
The conversion of N-acylpyrazoles into β-keto esters was accomplished efficiently by the treatment with α-bromo esters and zinc dust.Using this Reformatsky reaction of N-acylpyrazoles, 4-(protected amino)-3-oxoalkanoic acid derivatives were conveniently prepared as the key intermediates in the synthesis of statines.
A new method for the regioselective synthesis of β-enamino acid derivatives
Fustero, Santos,Diaz, Ma. Dolores,Carlon, Raquel Perez
, p. 725 - 728 (2007/10/02)
A mild, simple and efficient route to β-enamino imidazole carbonilic derivatives 3 by reaction of ketimines with N,N′-carbonyl diimidazole in the presence of boron triflouride as catalyst has been developed. The conversion of 3 to esters has also been explored.
