151647-54-0Relevant articles and documents
Reductive ipso-radical cyclization onto aromatic rings of five-membered alicyclic amino acids bearing N-(2-phenyl)benzoyl groups by photoinduced electron transfer promoted decarboxylation
Yamada, Tomoaki,Ozaki, Yui,Yamawaki, Mugen,Sugiura, Yoshihiko,Nishino, Kana,Morita, Toshio,Yoshimi, Yasuharu
, p. 835 - 838 (2017)
A new radical cyclization has been developed for the one-step synthesis of spiro dihydroisoquinolinone derivatives from alicyclic amino acids bearing N-(2-phenyl)benzoyl groups through photoinduced electron transfer (PET)-promoted decarboxylation. Reductive ipso-radical cyclization onto a benzene ring by an alkyl radical is achieved under mild conditions for the first time, although the substrates are limited to five-membered aliphatic carboxylic acids bearing N-(2-phenyl)benzoyl groups.
Metal-free approach for hindered amide-bond formation with hypervalent iodine(iii) reagents: application to hindered peptide synthesis
Lee, Hyo-Jun,Huang, Xiao,Sakaki, Shigeyoshi,Maruoka, Keiji
supporting information, p. 848 - 855 (2021/02/09)
A new bio-inspired approach is reported for amide and peptide synthesis using α-amino esters that possess a potential activating group (PAG) at the ester residue. To activate the ester functionality under mild metal-free conditions, we exploited the facile dearomatization of phenols with hypervalent iodine(iii) reagents. Using a pyridine-hydrogen fluoride complex, highly reactive acyl fluoride intermediates can be successfully generated, thereby allowing for the smooth formation of sterically hindered amides and peptides from bulky amines and α-amino esters, respectively.
Efficiency Enhancement of a Photocatalytic Decarbonylation of an Aminocyclopropenone by Benzothiophene Substitution
Mishiro, Kenji,Nomura, Mitsuki,Furuyama, Taniyuki,Kunishima, Munetaka
, p. 3625 - 3636 (2021/03/03)
To improve the efficiency of the photocatalytic decarbonylation of cyclopropenones, the effects of substituents on cyclopropenone were explored. A benzothiophene-substituted aminocyclopropenone exhibited significantly improved decarbonylation efficiency t
Method for preparing amide compound by photocatalysis of nitrogen-containing heterocyclic compound
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Paragraph 0047-0050; 0093; 0094, (2021/06/06)
The invention provides a method for preparing an amide compound by photocatalysis of a nitrogen-containing heterocyclic compound. The method comprises the following steps: mixing the nitrogen-containing heterocyclic compound, organic carboxylic acid and tetrahalomethane in a solvent, adding a catalyst, and reacting under the illumination condition to prepare the amide compound. According to the invention, the organic carboxylic acid, the nitrogen-containing heterocyclic compound containing reactive hydrogen on nitrogen atoms and the tetrahalomethane are used as raw materials, so the raw materials are wide in source, low in cost and high in safety, and large-scale production is facilitated; the halogen simple substance is co-produced in the reaction process, the added value is high, a large amount of waste is prevented from being generated, and the method has high atom economy and environmental friendliness; light conditions are adopted to replace traditional heating and high-pressure conditions, the reaction conditions are mild, environmental pollution is reduced, and the reaction cost is reduced; the method has the advantages of good substrate applicability, mild process conditions, environmental protection, simple process, simple and feasible operation method, and facilitation of popularization and application.
Photoenzymatic Reductions Enabled by Direct Excitation of Flavin-Dependent "Ene"-Reductases
Sandoval, Braddock A.,Clayman, Phillip D.,Oblinsky, Daniel G.,Oh, Seokjoon,Nakano, Yuji,Bird, Matthew,Scholes, Gregory D.,Hyster, Todd K.
supporting information, p. 1735 - 1739 (2021/01/25)
Non-natural photoenzymatic reactions reported to date have depended on the excitation of electron donor-acceptor complexes formed between substrates and cofactors within protein active sites to facilitate electron transfer. While this mechanism has unlocked new reactivity, it limits the types of substrates that can be involved in this area of catalysis. Here we demonstrate that direct excitation of flavin hydroquinone within "ene"-reductase active sites enables new substrates to participate in photoenzymatic reactions. We found that by using photoexcitation these enzymes gain the ability to reduce acrylamides through a single electron transfer mechanism.
Erratum: Photoenzymatic Reductions Enabled by Direct Excitation of Flavin-Dependent 'Ene'-Reductases (J. Am. Chem. Soc. (2021) 143:4 (1735-1739) DOI: 10.1021/jacs.0c11494)
Sandoval, Braddock A.,Clayman, Phillip D.,Oblinsky, Daniel G.,Oh, Seokjoon,Nakano, Yuji,Bird, Matthew,Scholes, Gregory D.,Hyster, Todd K.
supporting information, p. 3662 - 3662 (2021/04/09)
Support by the Department of Energy was inadvertently left out of the Acknowledgments and a coauthor's name was misspelled in the Supporting Information. The scientific part of the manuscript remains unchanged. The complete correct Acknowledgment paragraph is as follows.
N-Hydroxybenzimidazole as a structurally modifiable platform forN-oxyl radicals for direct C-H functionalization reactions
Hatanaka, Miho,Jiang, Julong,Maruoka, Keiji,Matsumoto, Akira,Sakamoto, Ryu,Sakurai, Shunya,Tsuzuki, Saori,Yoshii, Tomomi
, p. 5772 - 5778 (2020/06/22)
Methods for direct functionalization of C-H bonds mediated byN-oxyl radicals constitute a powerful tool in modern organic synthesis. While severalN-oxyl radicals have been developed to date, the lack of structural diversity for these species has hampered further progress in this field. Here we designed a novel class ofN-oxyl radicals based onN-hydroxybenzimidazole, and applied them to the direct C-H functionalization reactions. The flexibly modifiable features of these structures enabled facile tuning of their catalytic performance. Moreover, with these organoradicals, we have developed a metal-free approach for the synthesis of acyl fluoridesviadirect C-H fluorination of aldehydes under mild conditions.
Efficient cleavage of tertiary amide bonds: Via radical-polar crossover using a copper(ii) bromide/Selectfluor hybrid system
Maruoka, Keiji,Matsumoto, Akira,Wang, Zhe
, p. 12323 - 12328 (2020/12/08)
A novel approach for the efficient cleavage of the amide bonds in tertiary amides is reported. Based on the selective radical abstraction of a benzylic hydrogen atom by a CuBr2/Selectfluor hybrid system followed by a selective cleavage of an N-C bond, an acyl fluoride intermediate is formed. This intermediate may then be derivatized in a one-pot fashion. The reaction proceeds under mild conditions and exhibits a broad substrate scope with respect to the tertiary amide moiety as well as to nitrogen, oxygen, and carbon nucleophiles for the subsequent derivatization. Mechanistic studies suggest that the present reaction proceeds via a radical-polar crossover process that involves benzylic carbon radicals generated by the selective radical abstraction of a benzylic hydrogen atom by the CuBr2/Selectfluor hybrid system. Furthermore, a synthetic application of this method for the selective cleavage of peptides is described. This journal is
Environmentally benign decarboxylative: N-, O-, and S-Acetylations and acylations
Ghosh, Santanu,Purkait, Anisha,Jana, Chandan K.
supporting information, p. 8721 - 8727 (2020/12/30)
An operationally simple and general method for acetylation and acylation of a wide variety of substrates (amines, alcohols, phenols, thiols, and hydrazones) has been reported. Meldrum's acid and its derivatives have been used as an air-stable, non-volatile, cost-effective, and easy to handle acetylating/acylating agent. Easily separable byproducts (CO2 and acetone) allowed the isolation of analytically pure acetylated products without the requirement of work-up and any chromatography. This journal is
C-C Bond Cleavage of Unactivated 2-Acylimidazoles
Xin, Hai-Long,Pang, Bo,Choi, Jeesoo,Akkad, Walaa,Morimoto, Hiroyuki,Ohshima, Takashi
, p. 11592 - 11606 (2020/10/23)
2-Acylimidazoles are widely used as post-Transformable carboxylic acid equivalents in chemoselective and enantioselective reactions. Their transformations, however, require pretreatment with highly reactive, toxic methylating reagents to facilitate C-C bond cleavage. Here, we demonstrate that such pretreatment can be avoided and the C-C bond cleaved under neutral conditions without the use of additional reagents or catalysts. The scope of the reaction, including the use of products reported in the literature as substrates, and some mechanistic insights are described.
