Article
Chemistry, Multidisciplinary
Meng Juan Zhang, David James Young, Ji Long Ma, Guo Quan Shao
Summary: In this study, cluster-based metal organic frameworks were utilized as bifunctional visible photocatalysts for the photoinduced chemoselective transfer hydrogenation of unsaturated carbonyls to allylic alcohols. The nanoparticles served as photosensitizers and photocatalysts under blue LED irradiation, achieving highly chemoselective reduction of unsaturated carbonyl compounds with high catalytic activity. The photocatalytic system showed good recyclability without significant loss of efficiency.
Article
Chemistry, Organic
Xiaolan Jiang, Xiaofeng Cui, Jinxun Chen, Qixing Liu, Yongsheng Chen, Haifeng Zhou
Summary: A chemoselective iridium-catalyzed transfer hydrogenation of α,β-unsaturated ketones was achieved in water, resulting in a series of 2-benzyl indanones and analogues with high yields and good functional group tolerance. The practicality of this approach was demonstrated through gram-scale synthesis.
TETRAHEDRON LETTERS
(2022)
Article
Chemistry, Organic
Danielle L. J. Pinheiro, Martin Nielsen
Summary: The chemoselective reduction of enamides to alpha-amino acids using Ru pincer complexes as catalysts and iPrOH and EtOH as H-donors and solvents is demonstrated. A range of alpha-amino acids is synthesized with good to excellent yields. Applications, large-scale synthesis, and a one-pot experiment are also reported. Deuterium-labeling experiments show high regioselectivity between the alpha- and beta-positions of the alkene unit.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Kaixia Jian, Bingnan Li, Shuxian Zhu, Qingqing Xuan, Qiuling Song
Summary: In this study, a catalyst-free and efficient method using H3N•BH3 for the chemoselective reduction of α,β-unsaturated cycloketones and acyclic α,β-unsaturated ketones is described. The method is expedient, green, and applicable.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Rakesh R. Behera, Surajit Panda, Rahul Ghosh, A. Ashis Kumar, Bidraha Bagh
Summary: Efficient catalytic hydrosilylation of nitroarenes to form aromatic amines under solvent-free conditions using a well-defined manganese(II)-NNO pincer complex with low catalyst loading is reported. The reaction offers a sustainable alternative to classical hydrogenation and has potential utility in the preparation of commercial drug molecules.
Article
Chemistry, Organic
Dingguo Song, Shiliang Wang, Weiwei Huang, Rong Chen, Fangyuan Hu, Lingxin Cheng, Xianghua Zhao, Fei Ling, Weihui Zhong
Summary: Alcohols and nitrile derivatives are important in organic and bioorganic chemistry, and can be obtained through borrowing hydrogen and dehydrogenative coupling strategies. This study reports a mild and general method for synthesizing alpha-alkyl nitriles and alpha,beta-substituted acrylonitriles under photoirradiation, with broad substrate scope and simple reaction conditions.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Tingting Wang, Rui Miao, Renshi Luo, Jiaxi Xu, Zhanhui Yang
Summary: The research demonstrates for the first time that furan-2-yl anions can serve as robust and efficient γ-oxo and γ-hydroxyl acyl anion equivalents for the conversion of aldehydes and ketones into trifunctionalized dihydroxylketones and hydroxyl diones through sequential nucleophilic addition, Achmatowicz rearrangement, and newly established iridium-catalyzed highly selective transfer hydrogenation reduction.
Article
Chemistry, Multidisciplinary
Jing Guan, Jianzhong Chen, Yicong Luo, Lisen Guo, Wanbin Zhang
Summary: A highly selective earth-abundant transition metal copper catalyst was used to achieve the asymmetric hydrogenation of C=O bonds of exocyclic α,β-unsaturated pentanones using H-2. The desired products were obtained with up to 99% yield and 96% enantiomeric excess (99% ee, after recrystallization). The mechanism of hydrogenation was explored through deuterium-labelling experiments and control experiments, revealing that the substrate's keto-enol isomerization rate is faster than that of hydrogenation and the Cu-H complex selectively catalyzes the asymmetric reduction of the carbonyl group. Computational results suggest that the multiple attractive dispersion interactions (MADI effect) between the catalyst with bulky substituents and substrate contribute to stabilizing transition states and reducing by-product formation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Bo Han, Hongmei Jiao, Rong Chen, Yuqi Zhang, Jijiang Wang
Summary: The first example of NHC (N-heterocyclic carbene) ligand-promoted reduction of imines and azobenzenes with a homogeneous silver catalyst is reported. The use of PhSiH3 induces hydrogenation of imines and azobenzenes, and the 1 mol% NHC-Ag precatalyst enables the retention of reducible functionalities and compatibility of sensitive groups, offering a mild and practical method for amine preparation with high turnover numbers (up to 9500). It has also been shown that the IPrAgCl/PhSiH3 combination is responsible for the selective C=O reduction of aldehyde and ketone analogues.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Jun-Jie Tian, Ning Liu, Qi-Fei Liu, Wei Sun, Xiao-Chen Wang
Summary: This study reports the successful direct asymmetric vinylogous Mannich reactions of acyclic alpha, beta-unsaturated ketones using chiral bicyclic bisborane catalysts. The strong Lewis acidity and steric bulk of the bisborane catalysts played crucial roles in achieving high yields and selectivities.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Sudakar Padmanaban, Gunniya Hariyanandam Gunasekar, Sungho Yoon
Summary: In this study, a heterogeneous, pincer-type Ru porous organometallic polymer (Ru-Macho-POMP) with a high surface area was prepared via direct heterogenization of a commercially available homogeneous pincer-type complex, Ru-Macho, using dichloromethane as the cross-linker through a Lewis acid-catalyzed Friedel-Crafts reaction. The Ru-Macho-POMP catalyst demonstrated high turnover frequency (TOF = 920 h(-1)), high turnover number (TON = 2750), high chemoselectivity (99%), and recyclability during the selective hydrogenation of alpha, beta-unsaturated carbonyl compounds.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Ramachandra Reddy Putta, Simin Chun, Seok Beom Lee, Junhwa Hong, Seung Hyun Choi, Dong-Chan Oh, Suckchang Hong
Summary: An iron catalyst system that achieves chemoselectivity between borrowing hydrogen and dehydrogenative coupling protocols by simply changing the base is reported. The system can selectively and efficiently convert a broad range of nitriles and alcohols to the corresponding products, with environmentally benign and atom-efficient characteristics.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Thomas Vielhaber, Christoph Topf
Summary: The study introduces a user-friendly and glove-box-free catalytic protocol for the hydrogenation of ketones and conjugated CC bonds of esters and nitriles using a manganese catalyst. The catalyst, assembled in situ from a [Mn(CO)(5)Br] precursor and 2-picolylamine, shows good to excellent yields in the presence of t-BuOK. This system offers a fast and atom-efficient access to secondary alcohols and saturated esters without the need for oxygen-sensitive and expensive phosphine-based ligands.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Applied
A. A. Philippov, A. M. Chibiryaev, O. N. Martyanov
Summary: Catalytic hydrogenation of mono-, di- and trinuclear aromatic compounds was studied under hydrogen transfer conditions using 2-PrOH as hydrogen donor and Raney nickel as catalyst at different temperatures, showing that isolated aromatic rings have low reactivity, which can enhance the selectivity of the reaction.
Article
Chemistry, Organic
Kalipada Jana, Isao Mizota, Armido Studer
Summary: Formal hydroperfluoroalkylation of enones is achieved through a two-step process involving conjugate hydroboration and subsequent radical perfluoroalkylation. Both reactions proceed under very mild conditions at room temperature, making the process convenient and efficient.
