6195-92-2Relevant academic research and scientific papers
Synthesis of Chiral Amines via a Bi-Enzymatic Cascade Using an Ene-Reductase and Amine Dehydrogenase
Fossey-Jouenne, Aurélie,Jongkind, Ewald P. J.,Mayol, Ombeline,Paul, Caroline E.,Vergne-Vaxelaire, Carine,Zaparucha, Anne
, (2021/12/23)
Access to chiral amines with more than one stereocentre remains challenging, although an increasing number of methods are emerging. Here we developed a proof-of-concept bi-enzymatic cascade, consisting of an ene reductase and amine dehydrogenase (AmDH), to afford chiral diastereomerically enriched amines in one pot. The asymmetric reduction of unsaturated ketones and aldehydes by ene reductases from the Old Yellow Enzyme family (OYE) was adapted to reaction conditions for the reductive amination by amine dehydrogenases. By studying the substrate profiles of both reported biocatalysts, thirteen unsaturated carbonyl substrates were assayed against the best duo OYE/AmDH. Low (5 %) to high (97 %) conversion rates were obtained with enantiomeric and diastereomeric excess of up to 99 %. We expect our established bi-enzymatic cascade to allow access to chiral amines with both high enantiomeric and diastereomeric excess from varying alkene substrates depending on the combination of enzymes.
Deciphering Reactivity and Selectivity Patterns in Aliphatic C-H Bond Oxygenation of Cyclopentane and Cyclohexane Derivatives
Martin, Teo,Galeotti, Marco,Salamone, Michela,Liu, Fengjiao,Yu, Yanmin,Duan, Meng,Houk,Bietti, Massimo
supporting information, p. 9925 - 9937 (2021/06/30)
A kinetic, product, and computational study on the reactions of the cumyloxyl radical with monosubstituted cyclopentanes and cyclohexanes has been carried out. HAT rates, site-selectivities for C-H bond oxidation, and DFT computations provide quantitative information and theoretical models to explain the observed patterns. Cyclopentanes functionalize predominantly at C-1, and tertiary C-H bond activation barriers decrease on going from methyl- and tert-butylcyclopentane to phenylcyclopentane, in line with the computed C-H BDEs. With cyclohexanes, the relative importance of HAT from C-1 decreases on going from methyl- and phenylcyclohexane to ethyl-, isopropyl-, and tert-butylcyclohexane. Deactivation is also observed at C-2 with site-selectivity that progressively shifts to C-3 and C-4 with increasing substituent steric bulk. The site-selectivities observed in the corresponding oxidations promoted by ethyl(trifluoromethyl)dioxirane support this mechanistic picture. Comparison of these results with those obtained previously for C-H bond azidation and functionalizations promoted by the PINO radical of phenyl and tert-butylcyclohexane, together with new calculations, provides a mechanistic framework for understanding C-H bond functionalization of cycloalkanes. The nature of the HAT reagent, C-H bond strengths, and torsional effects are important determinants of site-selectivity, with the latter effects that play a major role in the reactions of oxygen-centered HAT reagents with monosubstituted cyclohexanes.
Method for preparing cyclopentanone compound by aqueous phase hydrogenation rearrangement of furfural and derivative thereof
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Paragraph 0048-0052, (2021/01/20)
The invention provides a method for preparing a cyclopentanone compound by aqueous phase hydrogenation rearrangement of furfural and a derivative thereof, and belongs to the field of catalytic conversion of biomass resources. Specifically, a supported Ni3P catalyst converts furfural and a derivative thereof into a cyclopentanone compound in an H2 atmosphere, wherein the supported Ni3P catalyst provided by the invention is prepared by a deposition-precipitation chemical plating method. According to the invention, the catalyst obtained by the method is high in dispersity and small in particle size, and has high furfural and derivative conversion rate and cyclopentanone compound selectivity in the reaction of preparing cyclopentanone and derivatives thereof by aqueous phase hydrogenation rearrangement of furfural and derivatives thereof; and the furfural conversion rate and the cyclopentanone selectivity respectively reach 89.1% and 81.3% after the reaction is carried out for 1 hour at the pressure of 4 MPa H2 and the temperature of 160 DEG C.
Efficient Palladium(0) supported on reduced graphene oxide for selective oxidation of olefins using graphene oxide as a ‘solid weak acid’
Gao, Xi,Zhou, Jianhao,Peng, Xinhua
, p. 73 - 78 (2019/02/06)
Selective oxidation of olefin derivatives to ketones has made innovative development over palladium(0) supported on reduced graphene oxide. Compared to traditional Wacker oxidation, the novel method offers an economical and environment-friendly option by using graphene oxide (GO) as a ‘solid weak acid’ instead of classical homogeneous catalysts like H2SO4 and CF3COOH. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscopy images of Pd0/RGO showed that the nanoscaled Pd particles generated at the flake structure of reduced graphene oxide. Under optimized condition, up to 44 kinds of ketones with different structures can be prepared with excellent yields.
SYSTEMS AND METHODS FOR SYNTHESIS OF PHENOLICS AND KETONES
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Paragraph 0080-0088, (2018/11/21)
Embodiments herein relate to apparatus and systems for phenolic and ketone synthesis and methods regarding the same. In an embodiment, a method of producing phenolics and ketones is included. The method can specifically include forming a reaction mixture comprising nanocrystalline cellulose (NCC) and water. The method can also include contacting the reaction mixture with a metal oxide catalyst at a temperature of 350 degrees Celsius or higher and a pressure of at least about 3200 psi to form a reaction product mixture. The reaction product mixture can include at least about 20 wt. % phenolics and at least about 10 wt. % ketones as a percentage of the total mass of nanocrystalline cellulose (NCC). Other embodiments are also included herein.
Effect of Cp*Iridium(III) Complex and acid co-catalyst on conversion of furfural compounds to cyclopentanones or straight chain ketones
Xu, Yong-Jian,Shi, Jing,Wu, Wei-Peng,Zhu, Rui,Li, Xing-Long,Deng, Jin,Fu, Yao
, p. 266 - 273 (2017/07/13)
In this paper, Cp*Ir (III) Complex and acid co-catalyst system was developed. By using Cp*Ir and γ-Al2O3 (Lewis acid), 5-hydroxymethylfurfural (5-HMF) can be converted efficiently to 3-hydroxymethyl cyclopentanone (HCPN). Meanwhile, Cp*Ir and Br?nsted acid can promote conversion of 5-HMF to 1-Hydroxy-2,5-hexanedione (HHD). The effect of Lewis acid and Br?nsted acid on the hydrogenation of furan derivatives was studied. Mechanism of conversion of 5-HMF to HCPN was discussed in detail and mechanism proposed by our predecessors was revised. Instead of being an intermediate for the formation of HCPN, it is believed that, HHD is a product of another reaction pathway. HHD condensed via Aldol reaction to produce 3-methylcyclopenten-2-ol-1-one (MCP) instead of HCPN. Under the promotion of Lewis acid, 5-HMF firstly convert to the precursor of HHD. After that, the reaction is through 4 π-electrocyclic ring closure process and HCPN was formed ultimately. Furthermore, we found that our Cp*Ir and acid co-catalyst system is suitable for a variety of furfural compounds. By using Cp*Ir, Br?nsted acid can promote conversion of furfural compounds to straight chain ketones and Lewis acid can promote the rearrangement of furfural compounds to cyclopentanone derivatives.
Ni-based catalysts derived from a metal-organic framework for selective oxidation of alkanes
Zhou, Ying,Long, Jilan,Li, Yingwei
, p. 955 - 962 (2016/07/06)
Ni nanoparticles embedded in nitrogen-doped carbon (Ni@C-N) materials were prepared by thermolysis of a Ni-containing metal-organic framework (Ni-MOF) under inert atmosphere. The as-synthesized Ni@C-N materials were characterized by powder X-ray diffraction, N2 adsorption-desorption analysis, scanning electron microscopy, transmission electron microscopy, atomic absorption spectroscopy, and X-ray photoelectron spectroscopy. The MOF-derived Ni-based materials were then examined as heterogeneous catalysts for the oxidation of alkanes under mild reaction conditions. The Ni@C-N composites displayed high activity and selectivity toward the oxidation of a variety of saturated C-H bonds, affording the corresponding oxidation products in good-to-excellent yields. Furthermore, the catalysts could be recycled and reused for at least four times without any significant loss in activity and selectivity under the investigated conditions.
Production of 2,5-hexanedione and 3-methyl-2-cyclopenten-1-one from 5-hydroxymethylfurfural
Ren, Dezhang,Song, Zhiyuan,Li, Lu,Liu, Yunjie,Jin, Fangming,Huo, Zhibao
supporting information, p. 3075 - 3081 (2016/06/06)
A novel approach for the production of 2,5-hexanedione (HDN) and 3-methyl-2-cyclopenten-1-one (3-MCO) from 5-hydroxymethylfurfural (HMF) by water splitting with Zn is reported for the first time. The use of high temperature water (HTW) conditions is the key for the efficient conversion of HMF to HDN and 3-MCO. Parameters regarding the Zn amount, temperature and reaction time are optimized and HDN and 3-MCO are produced in 27.3% and 30.5% yields, respectively. The roles of HTW and ZnO obtained by oxidation of Zn in water for the conversion of HMF, together with intermediate structures, are discussed to understand the mechanism of the reaction.
Towards quantitative and scalable transformation of furfural to cyclopentanone with supported gold catalysts
Zhang, Gao-Shuo,Zhu, Ming-Ming,Zhang, Qi,Liu, Yong-Mei,He, He-Yong,Cao, Yong
, p. 2155 - 2164 (2016/04/19)
Given the vital importance of furfural (FFA) upgrading towards a sustainable bio-based economy, an eco-friendly aqueous route to produce a sole valuable product from FFA is highly desirable. We herein describe an efficient approach to quantitatively convert FFA into cyclopentanone (CPO) in neat water, employing H2 as the clean reductant and supported gold nanoparticles as a simple yet versatile catalyst. The use of anatase TiO2 featuring only mild Lewis acidic sites as the underlying support is essential, not only for preventing undesirable side reactions, but also for attaining high CPO selectivity. The feasibility of using biogenic CPO and CO2 as benign carbon sources to synthesize the industrially important feedstock dimethyl adipate is also demonstrated.
Copper nanoparticles on dichromium trioxide: A highly efficient catalyst from copper chromium hydrotalcite for oxidant-free dehydrogenation of alcohols
Zhu, Yaoqin,Shen, Mengnan,Xia, Yonggen,Lu, Ming
, p. 152 - 156 (2015/03/30)
Stable copper(0) nanoparticles supported on chromium (Cu(0)/Cr2O3) are prepared from the composite precursor copper chromium hydrotalcite. The resulting Cu(0)/Cr2O3 catalyst is first used in the selective dehydrogenation of alcohols to aldehydes. More impressively, these dehydrogenations are performed without oxidants and yields of products are high. The stability of Cu(0)/Cr2O3 is also assessed by studying its recoverability and reusability for up to five cycles.
