نتایج جستجو برای: rhodium

تعداد نتایج: 4139  

Journal: :Chemical communications 2007
Hiromichi Sato Tetsuaki Fujihara Yasushi Obora Makoto Tokunaga Junya Kiyosu Yasushi Tsuji

Novel rhodium(I) complexes with N-heterocyclic carbenes bearing a 2,3,4,5-tetraphenylphenyl and its higher dendritic frameworks were synthesized and the complexes were used as catalysts in rhodium-catalyzed hydrosilylation of alpha,beta-unsaturated ketones to show high 1,4-adduct selectivity.

Journal: :Chemical communications 2010
Lianghui Liu Mengmeng Yu Bradford B Wayland Xuefeng Fu

Selective oxidation of alcohol in water using molecular oxygen as the terminal oxidant is mediated by rhodium porphyrin complexes. Addition of methanol to an aqueous solution of (TSPP)Rh(III) resulted in observation of the key intermediate porphyrin rhodium(III) methoxide species. The activation parameters for betaC-H elimination of Rh-alkoxide were evaluated.

Journal: :Chemical communications 2012
Jeffrey S Arnold Gregory T Cizio Drew R Heitz Hien M Nguyen

We report the chiral diene ligated rhodium-catalyzed dynamic kinetic asymmetric transformation (DYKAT) of racemic secondary allylic trichloroacetimidates with a variety of N-methyl anilines, providing allylic N-methyl arylamines in high yields, regioselectivity, and enantiomeric excess. The rhodium-catalyzed DYKAT method addresses limitations previously associated with this particular class of ...

2014
Hamish B Hepburn Hon Wai Lam

Allylrhodium species generated from potassium allyltrifluoroborates can undergo isomerization by 1,4-rhodium(I) migration to give more complex isomers, which then react with cyclic imines to provide products with up to three new stereochemical elements. High enantioselectivities are obtained using chiral diene-rhodium complexes.

Journal: :Organic letters 2006
Patrick Y Toullec Richard B C Jagt Johannes G de Vries Ben L Feringa Adriaan J Minnaard

[reaction: see text] A general method for the catalytic 1,2-addition of aryl and alkenyl boronic acids to isatins is described using a rhodium(I)/triphenylphosphite catalyst. The application of this transformation allows the synthesis of a variety of 3-aryl-3-hydroxyoxindole building blocks in high yields. An enantioselective version of this reaction using a rhodium(I)/phosphoramidite system is...

Journal: :Chemical communications 2016
C L Pitman O N L Finster A J M Miller

Attempts to generate a proposed rhodium hydride catalytic intermediate instead resulted in isolation of (Cp*H)Rh(bpy)Cl (1), a pentamethylcyclopentadiene complex, formed by C-H bond-forming reductive elimination from the fleeting rhodium hydride. The hydride transfer ability of diene 1 was explored through thermochemistry and hydride transfer reactions, including the reduction of NAD(+).

Journal: :Topics in current chemistry 2012
Monica Carreira Maria Contel

In this review, we describe the papers and patents dealing with the fluorous biphasic system (FBS) hydrosilylation reactions reported to date. Despite the limited number of reports, the FBS hydrosilylation reaction has been extremely successful. In all cases fluorous monophosphines (either alkylic or perfluoroalkylsilyl-substituted derivatives of triphenylphosphine) have been employed as ligand...

Journal: :Angewandte Chemie 2017
Tomoya Namba Susumu Kawauchi Yu Shibata Hiroshi Kanno Ken Tanaka

It is shown that a cationic rhodium(I)/biphep complex catalyzes the cycloisomerization of 2-(alkynylsilylethynyl)phenols, leading to alkynylmethylidene-benzoxasiloles through concomitant silicon and carbon migration. This unprecedented cycloisomerization presumably proceeds via the formation of rhodium vinylidenes through 1,2-silicon migration, followed by 1,3-carbon (alkyne) migration via the ...

Journal: :Organic letters 2001
A R Kennedy M H Taday J D Rainier

[reaction: see text] This letter describes the insertion of rhodium carbenoids into thioindoles. C-10 thioindoles undergo fragmentation-coupling reactions when exposed to rhodium carbenoids. In an analogous fashion, ketoester- and malonate-substituted carbenoids have been found to insert into C-2 thioindoles. In contrast, vinylogous carbenoids were found to alkylate C-2 thioindoles at C-3.

Journal: :Chemical communications 2015
Ryo Shintani Hiroki Kurata Kyoko Nozaki

Rhodium-catalyzed intramolecular alkynylsilylation of alkynes is described. The reaction proceeds through syn-insertion by a cationic rhodium/triarylphosphine catalyst, representing the first alkynylsilylation of alkynes via the cleavage of a C(sp)-Si bond by transition-metal catalysis. A highly enantioselective variant is also described for the creation of a silicon stereogenic center.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید