1610-29-3Relevant articles and documents
Copper(i) pyrimidine-2-thiolate cluster-based polymers as bifunctional visible-light-photocatalysts for chemoselective transfer hydrogenation of α,β-unsaturated carbonyls
Zhang, Meng Juan,Young, David James,Ma, Ji Long,Shao, Guo Quan
, p. 14899 - 14904 (2021/05/19)
The photoinduced chemoselective transfer hydrogenation of unsaturated carbonyls to allylic alcohols has been accomplished using cluster-based MOFs as bifunctional visible photocatalysts. Assemblies of hexanuclear clusters [Cu6(dmpymt)6] (1, Hdmpymt = 4,6-dimethylpyrimidine-2-thione) as metalloligands with CuI or (Ph3P)CuI yielded cluster-based metal organic frameworks (MOFs) {[Cu6(dmpymt)6]2[Cu2(μ-I)2]4(CuI)2}n (2), {[Cu6(dmpymt)6]2[Cu2(μ-I)2]4}n (3), respectively. Nanoparticles (NPs) of 2 and 3 served both as photosensitizers and photocatalysts for the highly chemoselective reduction of unsaturated carbonyl compounds to unsaturated alcohols with high catalytic activity under blue LED irradiation. The photocatalytic system could be reused for several cycles without any obvious loss of efficiency.
Reduction of carbonyl compounds via hydrosilylation catalyzed by well-defined PNP-Mn(I) hydride complexes
Weber, Stefan,Iebed, Dina,Glatz, Mathias,Kirchner, Karl
, p. 635 - 639 (2021/06/17)
Reduction reactions of unsaturated compounds are fundamental transformations in synthetic chemistry. In this context, the reduction of polarized double bonds such as carbonyl or C=C motifs can be achieved by hydrogenation reactions. We describe here a highly chemoselective Mn(I)-based PNP pincer catalyst for the hydrosilylation of aldehydes and ketones employing polymethylhydrosiloxane (PMHS) as inexpensive hydrogen donor. Graphic abstract: [Figure not available: see fulltext.]
Zeolite-Encaged Isolated Platinum Ions Enable Heterolytic Dihydrogen Activation and Selective Hydrogenations
Dai, Weili,Deng, Xin,Guan, Naijia,Li, Landong,Liu, Runze,Ma, Ding,Qin, Bin,Qin, Xuetao,Wu, Guangjun
supporting information, p. 20898 - 20906 (2021/12/14)
Understanding the unique behaviors of atomically dispersed catalysts and the origin thereof is a challenging topic. Herein, we demonstrate a facile strategy to encapsulate Ptδ+ species within Y zeolite and reveal the nature of selective hydrogenation over a Pt@Y model catalyst. The unique configuration of Pt@Y, namely atomically dispersed Ptδ+ stabilized by the surrounding oxygen atoms of six-membered rings shared by sodalite cages and supercages, enables the exclusive heterolytic activation of dihydrogen over Ptδ+···O2- units, resembling the well-known classical Lewis pairs. The charged hydrogen species, i.e., H+ and Hδ-, are active reagents for selective hydrogenations, and therefore, the Pt@Y catalyst exhibits remarkable performance in the selective hydrogenation of α,β-unsaturated aldehydes to unsaturated alcohols and of nitroarenes to arylamines.
CoOx@Co Nanoparticle-based Catalyst for Efficient Selective Transfer Hydrogenation of α,β-Unsaturated Aldehydes
Gong, Wanbing,Han, Miaomiao,Chen, Chun,Lin, Yue,Wang, Guozhong,Zhang, Haimin,Zhao, Huijun
, p. 1019 - 1024 (2019/12/27)
Currently, developing simple and effective catalysts for selective hydrogenation of α,β-unsaturated aldehydes to unsaturated alcohols is challenging. Herein, an efficient CoOx-shell/Co-core structured nanoparticle catalyst is synthesized by a facile ultrasonic-assisted carbothermal reduction method. The resultant catalyst exhibits outstanding catalytic performance toward the selective transfer hydrogenation of a wide spectrum of α,β-unsaturated aldehydes into corresponding unsaturated alcohols with over 90 % selectivity. This is the simplest nonprecious metal catalyst to be reported for the selective hydrogenation of unsaturated aldehydes.
Method for synthesizing unsaturated primary alcohol
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Paragraph 0074-0078, (2019/08/20)
The invention discloses a method for synthesizing an unsaturated primary alcohol. The method comprises the following steps: adding an unsaturated aldehyde, a transition metal catalyst iridium complexand isopropyl alcohol in a reaction container, heating the reaction mixture in an oil bath, carrying out a reaction for a plurality of hours, then carrying out cooling to room temperature, removing the solvent by rotating evaporation, and then carrying out column separation to obtain the target compound. According to the invention, the unsaturated aldehyde is used as a raw material, isopropyl alcohol is used as a hydrogen source and the solvent, and the unsaturated primary alcohol is generated through hydrogen transfer under participation of the transition metal iridium catalyst. The method has the following remarkable advantages: 1) the reaction temperature is low; 2) cheap, safe and non-toxic isopropanol is used; 3) the catalyst usage amount is low, and reaction atom economy is high; and4) selectivity is good. Therefore, the method meets the requirements of green chemistry and has a wide development prospect.
Development of a novel secondary phosphine oxide-ruthenium(II) catalyst and its application for carbonyl reduction
Tan, Xuefeng,Zeng, Weijun,Zhang, Xiaoyong,Chung, Lung Wa,Zhang, Xumu
supporting information, p. 535 - 538 (2018/01/19)
A secondary phosphine oxide-phosphine mixed tridentate ligand and its ruthenium complex have been developed. This complex shows excellent catalytic activity for carbonyl reduction, especially for the reduction of α,β-unsaturated aldehydes. The turnover number and selectivity can reach up to 36500 and 99%, respectively. Control experiments and DFT calculations supported an outer-sphere mechanism during the hydrogenation reaction.
Switchable Chemoselective Transfer Hydrogenations of Unsaturated Carbonyls Using Copper(I) N-Donor Thiolate Clusters
Zhang, Meng-Juan,Tan, Da-Wei,Li, Hong-Xi,Young, David James,Wang, Hui-Fang,Li, Hai-Yan,Lang, Jian-Ping
, p. 1204 - 1215 (2018/02/09)
Unsaturated alcohols and saturated carbonyls are important chemical, pharmaceutical, and biochemical intermediates. We herein report an efficient transfer hydrogenation protocol in which conversion of unsaturated carbonyl compounds to either unsaturated alcohols or saturated carbonyls was catalyzed by Cu(I) N-donor thiolate clusters along with changing hydrogen source (isopropanol or butanol) and base (NaOH or K2CO3). Mechanistic studies supported by DFT transition state modeling indicate that such a chemoselectivity can be explained by the relative concentrations of Cu(I) monohydride and protonated Cu(I) hydride complexes in each catalytic system.
Transfer Hydrogenation of Aldehydes and Ketones with Isopropanol under Neutral Conditions Catalyzed by a Metal-Ligand Bifunctional Catalyst [Cp?Ir(2,2′-bpyO)(H2O)]
Wang, Rongzhou,Tang, Yawen,Xu, Meng,Meng, Chong,Li, Feng
, p. 2274 - 2281 (2018/02/23)
A Cp?Ir complex bearing a functional bipyridonate ligand [Cp?Ir(2,2′-bpyO)(H2O)] was found to be a highly efficient and general catalyst for transfer hydrogenation of aldehydes and chemoselective transfer hydrogenation of unsaturated aldehydes with isopropanol under neutral conditions. It was noteworthy that many readily reducible or labile functional groups such as nitro, cyano, ester, and halide did not undergo any change under the reaction conditions. Furthermore, this catalytic system exhibited high activity for transfer hydrogenation of ketones with isopropanol. Notably, this research exhibited new potential of metal-ligand bifunctional catalysts for transfer hydrogenation.
Hydrogenation and Reductive Amination of Aldehydes using Triphos Ruthenium Catalysts
Christie, Francesca,Zanotti-Gerosa, Antonio,Grainger, Damian
, p. 1012 - 1018 (2018/01/27)
An air-stable and readily accessible ruthenium dihydride complex catalyses aldehyde hydrogenation under neutral conditions. A high activity has been shown in a number of examples, and solvent-free conditions are also applicable, which favours industrial-scale applications. The catalyst has also been demonstrated to be active at low catalyst loadings for the reductive amination of aldehydes under mildly acidic conditions. A number of examples of chemoselectivity challenges are also presented in which the catalyst does not reduce carbon?halogen groups, alkene or ketone functionality. The advantage of using the pre-formed complex, Triphos-Ru(CO)H2 (1), over in situ formed catalysts from Triphos and Ru(acac)3 (acac=acetylacetonate) is also shown in terms of both chemoselectivity and activity, in particular this can be seen if low reaction temperatures are used.
Tridentate phosphine ligand, catalyst and preparation method and application thereof
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Paragraph 0052-0054, (2017/12/30)
The invention belongs to the field of asymmetric catalysis, and discloses tridentate phosphine ligand which is of a structure of formula I as shown in the specification, wherein R is aryl or substituted aryl. The invention further discloses a catalyst prepared from the ligand. The catalyst is of a structure of formula II as shown in the specification, wherein R is aryl or substituted aryl, and L is mono-phosphine ligand. The invention further discloses application of the catalyst in a catalytic reduction reaction. The invention provides a tridentate phosphine ligand which is novel in structure, and a ruthenium complex of the tridentate phosphine ligand. carbonyl compounds, namely aldehyde and ketone, particularly alpha,beta-unsaturated aldehyde, are reduced by using the ruthenium complex, and very good reaction activity and selectivity are achieved.
