10396-80-2Relevant academic research and scientific papers
Catalytic Function of Cobalt(III) Complexes with N,N'-Disalicylideneethylenediamine on Oxygenation of t-Butylphenols
Aimoto, Yuko,Kanda, Wakako,Meguro, Sadatoshi,Miyahara, Yuji
, p. 646 - 650 (1985)
Catalytic oxygenation of t-butylphenols has been examined with the cobalt(III) complexes with N,N'-disalicylideneethylenediamine (H2salen), K, Na, K, PF6, and PF6.The CO3-complex showed a high catalytic activity while the other complexes a low or no catalytic activity.Based on electronic and ESR spectral investigation, it has been shown that the reaction is initiated by the direct oxidation of t-butylphenols by the CO3-complex through a phenolatocobalt(III) intermediate.
Br?nsted acid-catalyzed radical C[sbnd]H functionalization of acetone with N-allyl anilines to give 3-(3-oxobutyl)indolines
Wang, Xiufang,Zhao, Xiaohui,Li, Xiulan,Huo, Bojie,Dong, Ying,Liang, Deqiang,Ma, Yinhai
, p. 1306 - 1310 (2019)
K2S2O8 was unprecedentedly used instead of tert-butyl hydroperoxide (TBHP) in Br?nsted acid-assisted catalytic strategy for ketonic radical generation, and the first Br?nsted acid-catalyzed radical C[sbnd]H functionalizati
Rapid conversion of phenols to p-benzoquinones under acidic conditions with lead dioxide
Omura, Kanji
, p. 1145 - 1148 (1998)
Treatment of 4-unsubstituted and 4-halogenated phenols with PbO2 and 70% HClO4 in AcOH afforded the corresponding p-benzoquinones in fair to high yields. The oxidation of 4-substituted 2,6-di-tertbutylphenols 6 with PbO2 and 70% HClO4 in acetone gave 2,6-di-tert-butyl-p-benzoquinone (2).
The Oxidation of 2,6-Di-tert-butyl-4-methylphenol Using Hydrogen Peroxide-Heteropolyacid System
Shimizu, Masao,Orita, Hideo,Hayakawa, Takashi,Watanabe, Yoshihito,Takehira, Katsuomi
, p. 1835 - 1837 (1990)
The oxidation of 2,6-di-tert-butyl-4-methylphenol (1) with hydrogen peroxide in the presence of heteropolyacids was carried out in acetic acid to give 2,6-di-tert-butyl-4-hydroperoxy-4-methyl-2,5-cyclohexadien-1-one (2), 2,6-di-tert-butyl-4-hydroxy-4-methyl-2,5-cyclohexadien-1-one (3), and 2,6-di-tert-butyl-p-benzoquinone (4).Conversion of 2 into 4 under acidic conditions suggests that 2 could be a precursor of 4.The oxidation mechanism of phenols was discussed based on isolated intermediates.
A novel m-CPBA oxidation: p-quinols and epoxyquinols from phenols
Solaja, Bogdan A.,Milic, Dragana R.,Gasic, Miroslav J.
, p. 3765 - 3768 (1996)
Steroidal quinols were obtained on large scale in 50-57% yield, together with syn-epoxyquinols. The reaction conditions can be adjusted to afford only the corresponding steroidal epoxyquinol in 51-54% yield.
Oxidation of substituted phenols with chlorine dioxide
Loginov,Chukicheva,Kuchin
, p. 1501 - 1503 (2011)
Chlorine dioxide was used to oxidize sterically hindered phenols and their derivatives (2,6-di-tert-butylphenol, 2,6-diisobornylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,6-diisobornyl-4-methylphenol, and 3,5-diisobornyl-4-hydroxybenzaldehyde) in organic solvent. Pleiades Publishing, Ltd., 2011.
OXYDATION SELECTIVE EN PARA DES PHENOLS PAR UN COMPLEXE CUIVRIQUE OXYDANT
Capdevielle, Patrice,Maumy, Michel
, p. 5611 - 5614 (1983)
Oxidation of phenols by molecular oxygen in the presence of the μ-oxo cupric catalyst Cu4Cl4O2 (CH3CN)3 (A), can be selectively directed to give either oxidative coupling or para-hydroxylation (p-quinols or p-quinones) products by the choice of the (A)/(phenol) ratio.The mechanism is discussed and a -OH ligand transfer from CuII to the phenolic para position is proposed.
Peroxidation of 3,4-dihydro-1,4-benzoxazin-2-ones
Bao, Xiazhen,Huo, Congde,Wang, Jiayuan,Wang, Jie
, p. 3895 - 3898 (2020)
The sp3-C-H peroxidation of 3,4-dihydro-1,4-benzoxazin-2-ones was achieved under mild and simple catalyst-free reaction conditions. A range of biologically important alkylated benzoxazinone peroxides are synthesized in high yield with a good functional group tolerance. The C(sp3)-OO bond was constructed efficiently and could be further converted into C(sp3)-C(sp3), C(sp3)-C(sp2), C(sp3)-C(sp), C-P and CO bonds by late-stage functional group transformations.
Continuous Process Improvement in the Manufacture of Carfilzomib, Part 1: Process Understanding and Improvements in the Commercial Route to Prepare the Epoxyketone Warhead
Dornan, Peter K.,Anthoine, Travis,Beaver, Matthew G.,Cheng, Guilong Charles,Cohen, Dawn E.,Cui, Sheng,Lake, William E.,Langille, Neil F.,Lucas, Susan P.,Patel, Jenil,Powazinik, William,Roberts, Scott W.,Scardino, Chris,Tucker, John L.,Spada, Simone,Zeng, Alicia,Walker, Shawn D.
, p. 481 - 489 (2020)
Epoxyketone 4 is an isolated intermediate in the manufacturing route to the commercial proteasome inhibitor carfilzomib (Kyprolis). Commercial process development and optimization efforts toward the preparation of epoxyketone 4 highlighted several opportunities for process improvement. In this article, three case studies are presented that demonstrate how a detailed understanding of the reaction mechanism led to improvements that increased the overall robustness of the process. In the first case study, the mechanism of racemization of an α-chiral enone was investigated, resulting in the development of an improved aqueous workup procedure. Next, the stability of a bleach/pyridine mixture used for the step 3 epoxidation reaction was studied, leading to the identification of pyridine as a key raw material and improved reaction conditions and control strategy to meet the conversion target. Finally, oxidized butylated hydroxytoluene (oBHT) was identified as an impurity arising from the use of BHT-stabilized tetrahydrofuran in steps preceding the oxidation. The process understanding obtained from these investigations led to the implementation of process improvements that improved the robustness of the process. The development of a second-generation route to 4 is the subject of part 2 in this series (DOI: 10.1021/acs.oprd.0c00052).
Visible light-mediated, rose Bengal-catalyzed oxidative radical C[sbnd]H cyclization of alkyl 1,1′-biaryl-2-ones: An efficient synthesis of 10-alkylphenanthren-9-ols in water
Natarajan, Palani,Kumar, Naveen,Chaudhary, Renu,Venugopalan, Paloth
, (2020)
A visible light-mediated (blue LED: λ = 455 ± 10 nm), rose bengal-catalyzed intramolecular cycloaromatization reaction of alkyl 1, 1′-biaryl-2-ones for the synthesis of 10-alkylphenanthren-9-ols in water under open air atmosphere at ambient conditions has been developed. Experimental studies demonstrate that the reaction proceeded via a radical pathway. This protocol is applicable to a wide variety of substrates giving expected 10-alkylphenanthren-9-ols in good yields, appropriate for the gram-scale synthesis, atom economy, and eco-friendly as compared to literature reported methodology for the preparation of phenanthrol derivatives. Moreover, to the best of our knowledge, no instance has hitherto been accounted on the visible light-induced transformation of readily available alkyl 1,1′-biaryl-2-ones to 10-alkylphenanthren-9-ols.
