Unexpected High Regioselectivity in Rh-Catalyzed Homogeneous Hydrogenation of Naphthylene Derivatives
Zhongsheng Cai1,2, Xiangqing Feng1,2, Wei Meng1,2
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing100190, China.
Abstract:
A highly regioselective homogeneous hydrogenation of naphthalene derivatives has been successfully achieved using a biphosphine/rhodium catalytic system. This protocol enables selective reduction of the nonfunctionalized ring for diverse naphthene derivatives including naphthols, ethers, naphthylamines, naphthalenes, and esters, delivering partially saturated products in 39-99% yields. Notably, precise regiodiscrimination was achieved even for 2-methylnaphthalene with subtle methyl substitution. Mercury and PvPy (poly(4-vinylpyridine)) poisoning tests suggest that the reaction likely occurs in a homogeneous manner.
More Related Videos
10:52Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
10:39Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
Related Concept Videos
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
02:36Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
02:35Regioselectivity of Electrophilic Additions-Peroxide Effect
02:13Reduction of Alkenes: Catalytic Hydrogenation
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...
01:25Radical Anti-Markovnikov Addition to Alkenes: Overview