30616-79-6Relevant academic research and scientific papers
Metal-Free Oxidative Condensation of Catechols, Aldehydes and NH4OAc towards Benzoxazoles
Dong, Jianyu,Geng, Furong,Su, Lebin,Wu, Shaofeng,Yin, Shuang-Feng,Zhou, Dan,Zhou, Yongbo
supporting information, p. 3607 - 3614 (2021/07/28)
Benzoxazoles extensively exist in biologically active compounds, natural products, pharmaceuticals and functional materials. Thus, facile and green synthesis of such valuable compounds from easily available substrates will make a contribution to drug, material, and fine chemistry. A method for the synthesis of benzoxazoles from catechols, aldehydes and ammonium acetate is developed using NaIO4 as oxidant under metal- and additive-free conditions. A broad range of benzoxazoles including some fluorescent whitening agents, JTP-426467 and tafamidis analogues are synthesized in 56–95% yields with outstanding functional group tolerance. Mechanistic investigations suggest that an interesting o-iminocyclohexa-diene alcohol intermediate is involved in the reaction. These salient features of the protocol make it an alternative for the synthesis of benzoxazoles. (Figure presented.).
ALPHA, BETA-UNSATURATED AMIDE COMPOUND
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Paragraph 1161; 1177, (2020/12/10)
An object of the present invention is to provide an α,β-unsaturated amide compound or a pharmaceutically acceptable salt or the like thereof having anticancer activity and the like. The α,β-unsaturated amide compound represented by the following formula (I) or a pharmaceutically acceptable salt or the like thereof has anticancer activity and the like: [wherein, "A" represents optionally substituted heterocyclic diyl, R1 represents hydrogen atom or optionally substituted lower alkyl, R2 represents optionally substituted aryl, optionally substituted cycloalkyl, optionally substituted aliphatic heterocyclic group or optionally substituted aromatic heterocyclic group, X represents -O-, -S-, -SO2-, -NRX1- (wherein, RX1 represents hydrogen atom or lower alkyl), -CHRX2- (wherein, RX2 represents hydrogen atom or hydroxy), -CH=CH-, -CO- or -NH-CO-, and n1 and n2 are the same or different, and each represents 0 or 1].
Base-Free Selective O-Arylation and Sequential [3,3]-Rearrangement of Amidoximes with Diaryliodonium Salts: Synthesis of 2-Substituted Benzoxazoles
Shi, Wei-Min,Li, Xiao-Hua,Liang, Cui,Mo, Dong-Liang
, p. 4129 - 4135 (2017/12/15)
A variety of functionalized 2-substituted benzoxazoles can be prepared in good yields from amidoximes and diaryliodonium salts by selective O-arylation and sequential [3,3]-rearrangement under metal-free conditions. O-arylation of amidoximes was promoted by 3 ? molecule sieves in the absence of a base and a sequential TFA-mediated [3,3]-rearrangement was used to synthesize 2-substituted benzoxazoles. Both of the O-aryl products and rearrangement products were compatible with a broad range of sensitive functional groups such as ester, aldehyde, nitro, vinyl, amine, and amide groups in addition to halides. A bidentate N-ligand with double benzoxazoles was prepared at gram-scale in two steps. (Figure presented.).
Organocatalytic syntheses of benzoxazoles and benzothiazoles using aryl iodide and oxone via C-H functionalization and C-O/S bond formation
Alla, Santhosh Kumar,Sadhu, Pradeep,Punniyamurthy, Tharmalingam
, p. 7502 - 7511 (2014/09/16)
An organocatalytic protocol for the syntheses of 2-substituted benzoxazoles and benzothiazoles is described from alkyl-/arylanilides and alkyl-/arylthioanilides using 1-iodo-4-nitrobenzene as catalyst and oxone as an inexpensive and environmentally safe terminal oxidant at room temperature in air via oxidative C-H functionalization and C-O/S bond formation. The procedure is simple and general and provides an effective route for the construction of functionalized 2-alkyl-/arylbenzoxazoles and 2-alkyl-/arylbenzothiazoles with moderate to high yields. The synthetic and mechanistic aspects have been described.
Synthesis of 2-arylbenzoxazoles through oxidation of C-H bonds adjacent to oxygen atoms
Gu, Lijun,Wang, Wei,Xiong, Yong,Huang, Xiangzhong,Li, Ganpeng
, p. 319 - 322 (2014/01/23)
A practical and simple synthesis of benzoxazoles from easily available substrates was developed. The protocol is triggered by an iron-catalyzed tandem oxidative process from simple ether derivatives. A practical and simple synthesis of benzoxazoles from easily available substrates is developed. The protocol is triggered by an iron-catalyzed tandem oxidative process from simple ether derivatives. Copyright
Synthesis of 2-Arylbenzoxazoles through Oxidation of C-H Bonds Adjacent to Oxygen Atoms
Gu, Lijun,Wang, Wei,Xiong, Yong,Huang, Xiangzhong,Li, Ganpeng
, p. 319 - 322 (2015/10/05)
A practical and simple synthesis of benzoxazoles from easily available substrates was developed. The protocol is triggered by an iron-catalyzed tandem oxidative process from simple ether derivatives.
A novel strategy for the construction of substituted benzoxazoles via a tandem oxidative process
Gu, Lijun,Jin, Cheng,Guo, Junming,Zhang, Lizhu,Wang, Wei
supporting information, p. 10968 - 10970 (2013/11/19)
A practical and simple synthesis of benzoxazoles from easily available substrates was developed. The protocol is triggered by an iron-catalyzed tandem oxidative process from simple toluene derivatives and 2-aminophenols. This method represents a straightforward approach to access substituted benzoxazoles. This journal is The Royal Society of Chemistry 2013.
Facile preparation of alkoxybenzoxazoles via direct SNAr on the benzoxazole ring
Germain, Hervé,Harris, Craig S.,Vautier, Michel,Warin, Nicolas
supporting information; experimental part, p. 554 - 556 (2010/10/02)
The synthesis of alkoxybenzoxazoles is in general quite challenging. During our investigation, we discovered that C-4 and C-7 fluoro precursors undergo SNAr with alkoxides affording moderate to excellent yields of substituted product.
Synthesis of 2-arylbenzoxazoles by copper-catalyzed intramolecular oxidative C-O coupling of benzanilides
Ueda, Satoshi,Nagasawa, Hideko
supporting information; experimental part, p. 6411 - 6413 (2009/03/11)
(Chemical Equation Presented) No need for additives: A wide variety of functionalized 2-arylbenzoxazoles can be prepared with high functional-group tolerance and regioselectivity by a copper-catalyzed intramolecular oxidative C-O coupling of benzanilides. The catalytic cycle is completed by the regeneration of the copper catalyst using molecular oxygen as a terminal oxidant without the need for additives.
