نتایج جستجو برای: heterogeneous catalytic hydrogenation

تعداد نتایج: 208736  

Journal: :Chemical communications 2016
Chengcheng Tian Xiang Zhu Carter W Abney Ziqi Tian De-En Jiang Kee Sung Han Shannon M Mahurin Nancy M Washton Sheng Dai

The design and synthesis of metal-free heterogeneous catalysts for efficient hydrogenation remains a great challenge. Here we report a novel approach to create conjugated nanoporous polymers with efficient hydrogenation activities toward unsaturated ketones by leveraging the innate steric encumbrance. The steric bulk of the framework as well as the local sterics of the Lewis basic sites within ...

Journal: :Chemistry 2011
Ying Duan Mu-Wang Chen Zhi-Shi Ye Duo-Sheng Wang Qing-An Chen Yong-Gui Zhou

Tandem reactions and consecutive catalysis (or relay catalysis) have been receiving considerable attention in organic synthesis due to their abilities of constructing multiple new chemical bonds to build complex chiral molecules in a single operation. Transition-metal-catalyzed asymmetric hydrogenation is one of the most widely used and reliable catalytic methods for preparation of chiral molec...

Journal: :Chemistry, an Asian journal 2007
Mikihiro Takasaki Yukihiro Motoyama Kenji Higashi Seong-Ho Yoon Isao Mochida Hideo Nagashima

The reaction of three types of carbon nanofibers (CNFs; platelet: CNF-P, tubular: CNF-T, herringbone: CNF-H) with [Ru3(CO)12] in toluene heated at reflux provided the corresponding CNF-supported ruthenium nanoparticles, Ru/CNFs (Ru content = 1.1-3.8 wt %). TEM studies of these Ru/CNFs revealed that size-controlled Ru nanoparticles (2-4 nm) exist on the CNFs, and that their location was dependen...

2002
Douglas C. Elliott Christopher F. Wend Mikhail S. Alnajjar

A significant contribution to displacement of fossil petroleum utilization can be made through the use of renewable waste and byproduct material for commodity chemical production. One such opportunity is lactose recovered from cheese whey. Several routes for use have been considered. A process involving catalytic hydrolysis of the lactose, catalytic hydrogenation to produce the sugar alcohols, ...

2016
Racharla Krishna Chowdam Ramakrishna Keshav Soni

The efficient citral hydrogenation was achieved in aqueous media using Pd/CMS and alkali additives like K2CO3. The alkali concentrations, reaction temperature and the Pd metal content were optimized to enhance the citral hydrogenation under aqueous media. In the absence of alkali, citral hydrogenation was low and addition of alkali promoted to ~92% hydrogenation without reduction in the selecti...

Journal: :Physical chemistry chemical physics : PCCP 2014
Weichang Wu Zhimin Ao Tao Wang Changming Li Sean Li

An alternative approach for hydrogenation of silicene is proposed through applying an external electric field in order to reduce the reaction energy barrier based on density functional theory calculations. It is found that a positive perpendicular electric field F can act as a catalyst to reduce the energy barrier of H2 dissociative adsorption on silicene, which facilitates the hydrogenation of...

Journal: :Angewandte Chemie 2005
Duan Liu Wenzhong Gao Chunjiang Wang Xumu Zhang

Enantioselective hydrogenation of amino ketones catalyzed by Ru– or Rh–phosphine complexes provides an efficient method for the synthesis of enantiomerically active amino alcohols, a class of chiral compounds of great importance in pharmaceutical products. A recent challenging target inspired us to look for a practical solution for the enantioselective reduction of b-amino ketones with a second...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید