65407-95-6Relevant academic research and scientific papers
Cu-Catalyzed Synthesis of Benzoxazole with Phenol and Cyclic Oxime
Wang, Zheng-Hai,Wang, Dong-Hui
supporting information, p. 782 - 785 (2022/01/20)
A Cu-catalyzed straightforward synthesis of benzoxazoles from free phenols and cyclic oxime esters is reported. The mild reaction conditions tolerate various electron-withdrawing and electron-donating functional groups on both substrates, affording benzoxazoles in moderate to good yields. With this protocol, large-scale syntheses of Ezutromid and Flunoxaprofe in one or two steps are demonstrated. A catalytic mechanism, which includes Cu-catalyzed amination via inner-sphere electron transfer and consequent annulation, is proposed.
Delivering 2-Aryl Benzoxazoles through Metal-Free and Redox-Neutral De-CF3Process
Qiao, Xinxin,Zhao, Yong-De,Rao, Mingru,Bu, Zhan-Wei,Zhang, Guangwu,Xiong, Heng-Ying
, p. 13548 - 13558 (2021/10/01)
An unexpected cleavage of the Csp3-CF3 bond of CF3-hydrobenzoxazoles has been disclosed, affording a range of 2-aryl benzoxazoles under metal-free and redox-neutral conditions. This transformation has demonstrated broad substrate scope and good compatibility of functional groups. 2-Aryl benzothiazole and 2-aryl benzoimidazole could be smoothly assembled in the same manner. On the basis of preliminary mechanistic studies, base initiated and aromatization driven β-carbon elimination was considered to be the key step for the formation of 2. This reaction offers an alternative, facile, and sustainable route to access important 2-aryl benzoxazole motifs.
Synthesis of benzoxazoles via the copper-catalyzed hydroamination of alkynones with 2-aminophenols
Oshimoto, Kohei,Tsuji, Hiroaki,Kawatsura, Motoi
, p. 4225 - 4229 (2019/05/10)
We describe herein the synthetic method to benzoxazole derivatives via the copper-catalyzed hydroamination of alkynones with 2-aminophenols. The method produced a wide variety of functionalized benzoxazole derivatives in good yields. Preliminary mechanistic experiments revealed that the reaction would proceed through the copper-catalyzed hydroamination of alkynones and the sequential intramolecular cyclization of β-iminoketones/elimination of acetophenone promoted by the copper catalyst.
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
supporting information, 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.).
TREATMENT OF DUCHENNE MUSCULAR DYSTROPHY
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Page/Page column 51; 53, (2008/06/13)
There are disclosed compound of Formula (1): A1, A2, A3 and A4 which may be the same or different, represent N or CR1, X is a divalent group selected from O, S(O)n, C=W, NR4, NC(=O)R5 and CR6R7, W is O, S, NR20, Y is N or CR8, one of R4, R5, R6, R8, R9 and NR20 represents - L -R3, in which L is a single bond or a linker group, additionally, R1, R3 - R9, which may be the same or different, independently represent hydrogen or a substituent and R20 represents hydrogen, hydroxyl, alkyl optionally substituted by aryl, alkoxy optionally substituted by aryl, aryl, CN, optionally substituted alkoxy, optionally substituted aryloxy, optionally substitute alkanoyl, optionally substituted aroyl, NO2, NR30R31, in which R30 and R31, which may be the same or different, represent hydrogen, optionally substituted alkyl or optionally substituted aryl; additionally, one of R30 and R31 may represent optionally substituted alkanoyl or optionally substituted aroyl, n represents an integer from 0 to 2, in addition, when an adjacent pair of A1 - A4 each represent CR1, then the adjacent carbon atoms, together with their substituents may form a ring B, when X is CR6R7, R6 and R7, together with the carbon atom to which they are attached may form a ring C, or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for the therapeutic and/or prophylactic treatment of Duchenne muscular dystrophy, Becker muscular dystrophy or cachexia.
A simple and efficient one step synthesis of benzoxazoles and benzimidazoles from carboxylic acids
Wang, Ying,Sarris, Kathy,Sauer, Daryl R.,Djuric, Stevan W.
, p. 4823 - 4826 (2007/10/03)
Benzoxazoles or benzimidazoles can be rapidly and efficiently synthesized from a variety of carboxylic acids with 2-aminophenols or 1,2-phenylenediamines in one simple step, respectively. The use of commercially available PS-PPh3 resin combined with microwave heating delivered a variety of benzoxazoles and benzimidazoles in high yields and purities.
