579-43-1Relevant articles and documents
Diastereoselective Ce(III)-catalyzed pinacol couplings of aldehydes
Groth,Jeske
, p. 129 - 131 (2001)
Aliphatic and aromatic aldehydes were converted into the corresponding pinacoles by using different cerium catalysts. Ce(OtBu)3 proved to be superior over other cerium(III) catalysts. Especially the highly diastereoselective pinacol coupling of sterically non demanding aldehydes such as hexanal is remarkable.
Efficient splitting of alcohols into hydrogen and C–C coupled products over ultrathin Ni-doped ZnIn2S4 nanosheet photocatalyst
Li, Jing-Yu,Qi, Ming-Yu,Xu, Yi-Jun
, p. 1084 - 1091 (2022/03/15)
Integrating selective organic synthesis with hydrogen (H2) evolution in one photocatalytic redox reaction system sheds light on the underlying approach for concurrent employment of photogenerated electrons and holes towards efficient production of solar fuels and chemicals. In this work, a facile one-pot oil bath method has been proposed to fabricate a noble metal-free ultrathin Ni-doped ZnIn2S4 (ZIS/Ni) composite nanosheet for effective solar-driven selective dehydrocoupling of benzyl alcohol into value-added C–C coupled hydrobenzoin and H2 fuel, which exhibits higher performance than pure ZIS nanosheet. The remarkably improved photoredox activity of ZIS/Ni is mainly attributed to the optimized electron structure featuring narrower band gap and suitable energy band position, which facilitates the ability of light harvesting and photoexcited charge carrier separation and transfer. Furthermore, it has been demonstrated that it is feasible to employ ZIS/Ni for various aromatic alcohols dehydrocoupling to the corresponding C–C coupled products. It is expected that this work can stimulate further interest on the establishment of innovative photocatalytic redox platform coupling clean solar fuels synthesis and selective organic conversion in a sustainable manner.
Asymmetric hydrogenation of 1,4-diketones: facile synthesis of enantiopure 1,4-diarylbutane-1,4-diols
Huang, Fanping,Shao, Pan-Lin,Song, Jingyuan,Wang, Jiang,Zhang, Xumu
supporting information, p. 262 - 265 (2022/01/06)
Owing to the biological significance and great synthetic value of 1,4-diarylbutane-1,4-diols and their derivatives, increasingly considerable attention has been paid to developing effective synthetic methods for chiral 1,4-diarylbutane-1,4-diols. We herei
A Colorimetric Method for Quantifying Cis and Trans Alkenes Using an Indicator Displacement Assay
Valenzuela, Stephanie A.,Crory, Hannah S. N.,Yao, Chao-Yi,Howard, James R.,Saucedo, Gabriel,de Silva, A. Prasanna,Anslyn, Eric V.
, p. 13819 - 13823 (2021/05/17)
A colorimetric indicator displacement assay (IDA) amenable to high-throughput experimentation was developed to determine the percentage of cis and trans alkenes. Using 96-well plates two steps are performed: a reaction plate for dihydroxylation of the alkenes followed by an IDA screening plate consisting of an indicator and a boronic acid. The dihydroxylation generates either erythro or threo vicinal diols from cis or trans alkenes, depending upon their syn- or anti-addition mechanisms. Threo diols preferentially associate with the boronic acid due to the creation of more stable boronate esters, thus displacing the indicator to a greater extent. The generality of the protocol was demonstrated using seven sets of cis and trans alkenes. Blind mixtures of cis and trans alkenes were made, resulting in an average error of ±2 % in the percentage of cis or trans alkenes, and implementing E2 and Wittig reactions gave errors of ±3 %. Furthermore, we developed variants of the IDA for which the color may be tuned to optimize the response for the human eye.
CBZ6 as a Recyclable Organic Photoreductant for Pinacol Coupling
Wang, Hua,Qu, Jian-Ping,Kang, Yan-Biao
supporting information, p. 2900 - 2903 (2021/05/05)
A recyclable organic photoreductant (1 mol % CBZ6)-catalyzed reductive (pinacol) coupling of aldehydes, ketones, and imines has been developed. Irradiated by purple light (407 nm) using triethylamine as an electron donor, a variety of 1,2-diols and 1,2-diamines could be prepared. The oxidation potential of the excited state of CBZ6 is established as -1.92 V (vs saturated calomel electrode (SCE)). The relative high reductive potential enables the reductive coupling of carbonyl compounds and their derivatives. CBZ6 can be prepared in gram scale and is acid/base- or air-stable. It could be applied in large-scale photoreductive synthesis and recovered in high yield after the reaction.
Ni2P Nanoalloy as an Air-Stable and Versatile Hydrogenation Catalyst in Water: P-Alloying Strategy for Designing Smart Catalysts
Fujita, Shu,Yamaguchi, Sho,Yamasaki, Jun,Nakajima, Kiyotaka,Yamazoe, Seiji,Mizugaki, Tomoo,Mitsudome, Takato
supporting information, p. 4439 - 4446 (2021/02/09)
Non-noble metal-based hydrogenation catalysts have limited practical applications because they exhibit low activity, require harsh reaction conditions, and are unstable in air. To overcome these limitations, herein we propose the alloying of non-noble metal nanoparticles with phosphorus as a promising strategy for developing smart catalysts that exhibit both excellent activity and air stability. We synthesized a novel nickel phosphide nanoalloy (nano-Ni2P) with coordinatively unsaturated Ni active sites. Unlike conventional air-unstable non-noble metal catalysts, nano-Ni2P retained its metallic nature in air, and exhibited a high activity for the hydrogenation of various substrates with polar functional groups, such as aldehydes, ketones, nitriles, and nitroarenes to the desired products in excellent yields in water. Furthermore, the used nano-Ni2P catalyst was easy to handle in air and could be reused without pretreatment, providing a simple and clean catalyst system for general hydrogenation reactions.
Metal-free thermal organocatalytic pinacol coupling of arylaldehydes using an isonicotinate catalyst with bis(pinacolato)diboron
Hanaya, Kengo,Higashibayashi, Shuhei,Sugai, Takeshi,Yasui, Masamichi
, p. 24652 - 24655 (2021/07/29)
The metal-free thermal organocatalytic pinacol coupling of arylaldehydes has been developed. The intermolecular coupling of arylaldehydes catalyzed byt-butyl isonicotinate with bis(pinacolato)diboron as the co-reducing agent afforded 1,2-diphenylethane-1,2-diols. This reaction was also applicable to the intramolecular coupling of 1,1′-biphenyl-2,2′-dicarbaldehydes to afford 9,10-dihydrophenanthrene-9,10-diols. Various functional groups were tolerated under this coupling condition.
A convenient pinacol coupling of diaryl ketones with B2pin2viapyridine catalysis
Jo, Junhyuk,Kim, Seonyul,Choi, Jun-Ho,Chung, Won-Jin
supporting information, p. 1360 - 1363 (2021/02/22)
A convenient, pyridine-boryl radical-mediated pinacol coupling of diaryl ketones is developed. In contrast to the conventional pinacol coupling that requires sensitive reducing metal, the current method employs a stable diboron reagent and pyridine Lewis base catalyst for the generation of a ketyl radical. The newly developed process is operationally simple, and the desired diols are produced with excellent efficiency in up to 99% yield within 1 hour. The superior reactivity of diaryl ketone was observed over monoaryl carbonyl compounds and analyzed by DFT calculations, which suggests the necessity of both aromatic rings for the maximum stabilization of the transition states.
Electrochemical Arylation of Aldehydes, Ketones, and Alcohols: from Cathodic Reduction to Convergent Paired Electrolysis
Zhang, Sheng,Li, Lijun,Li, Jingjing,Shi, Jianxue,Xu, Kun,Gao, Wenchao,Zong, Luyi,Li, Guigen,Findlater, Michael
supporting information, p. 7275 - 7282 (2021/03/01)
Arylation of carbonyls, one of the most common approaches toward alcohols, has received tremendous attention, as alcohols are important feedstocks and building blocks in organic synthesis. Despite great progress, there is still a great gap to develop an ideal arylation method featuring mild conditions, good functional group tolerance, and readily available starting materials. We now show that electrochemical arylation can fill the gap. By taking advantage of synthetic electrochemistry, commercially available aldehydes (ketones) and benzylic alcohols can be readily arylated to provide a general and scalable access to structurally diverse alcohols (97 examples, >10 gram-scale). More importantly, convergent paired electrolysis, the ideal but challenging electrochemical technology, was employed to transform low-value alcohols into more useful alcohols. Detailed mechanism study suggests that two plausible pathways are involved in the redox neutral α-arylation of benzylic alcohols.
Mo–Catalyzed One-Pot Synthesis of N-Polyheterocycles from Nitroarenes and Glycols with Recycling of the Waste Reduction Byproduct. Substituent-Tuned Photophysical Properties
Hernández-Ruiz, Raquel,Rubio-Presa, Rubén,Suárez-Pantiga, Samuel,Pedrosa, María R.,Fernández-Rodríguez, Manuel A.,Tapia, M. José,Sanz, Roberto
supporting information, p. 13613 - 13623 (2021/08/23)
A catalytic domino reduction–imine formation–intramolecular cyclization–oxidation for the general synthesis of a wide variety of biologically relevant N-polyheterocycles, such as quinoxaline- and quinoline-fused derivatives, and phenanthridines, is reported. A simple, easily available, and environmentally friendly dioxomolybdenum(VI) complex has proven to be a highly efficient and versatile catalyst for transforming a broad range of starting nitroarenes involving several redox processes. Not only is this a sustainable, step-economical as well as air- and moisture-tolerant method, but also it is worth highlighting that the waste byproduct generated in the first step of the sequence is recycled and incorporated in the final target molecule, improving the overall synthetic efficiency. Moreover, selected indoloquinoxalines have been photophysically characterized in cyclohexane and toluene with exceptional fluorescence quantum yields above 0.7 for the alkyl derivatives.
