Carbonylative Coupling of Alkyl Zinc Reagents with Benzyl Bromides Catalyzed by a Nickel/NN
<sub>2</sub>
Pincer Ligand Complex
作者:Thomas L. Andersen、Aske S. Donslund、Karoline T. Neumann、Troels Skrydstrup
DOI:10.1002/anie.201710089
日期:2018.1.15
An efficient catalytic protocol for the three‐component assembly of benzyl bromides, carbon monoxide, and alkyl zinc reagents to give benzyl alkyl ketones is described, and represents the first nickel‐catalyzed carbonylative coupling of two sp3‐carbon fragments. The method, which relies on the application of nickelcomplexed with an NN2‐type pincer ligand and a controlled release of CO gas from a solid
Direct Allylation of In Situ Generated Aldehyde Acyl Anions by Synergistic NHC and Palladium Catalysis
作者:Milind M. Ahire、Santosh B. Mhaske
DOI:10.1002/anie.201400623
日期:2014.7.1
The direct regioselective allylation of in situgeneratedaldehydeacylanions has been achieved by synergisticNHC and Pd catalysis. It provides an efficient access to valuable β,γ‐unsaturated ketones under mild reaction conditions starting from easily accessible allylic carbonates and aldehydes without any preactivation. The synergisticcatalysis method demonstrated herein adds a new dimension to
considerably: allylic trifluoroacetate gave the best result, while the corresponding acetates and trichloroacetates did not afford any acylation products at all. Stoichiometric reaction of 4a with 1 gave acylation product 3 with a formation of 5a and Pd(0), whereas no acylation reaction took place with the corresponding acetate complex [Pd(eta3-C6H5CH=CHCH2)(CH3COO)]2 (4b). A DFT calculation suggests that
Methods and compositions for inhibiting metal corrosion
申请人:Cassidy M. Juanita
公开号:US20050123437A1
公开(公告)日:2005-06-09
Methods and compositions are provided that inhibit the corrosion of metal surfaces by aqueous acid solutions. The inhibition is basically achieved by the addition of a reaction product of an alpha,beta-unsaturated aldehyde or ketone with a primary or secondary amine to the aqueous acid solution.
Selective Functionalization of a Variety of Hydrocarbon C(sp<sup>3</sup>)–H Bonds Initiated by Cp*W(NO)(CH<sub>2</sub>CMe<sub>3</sub>)(η<sup>3</sup>-CH<sub>2</sub>CHCHPh)
作者:Russell J. Wakeham、Rhett A. Baillie、Brian O. Patrick、Peter Legzdins、Devon C. Rosenfeld
DOI:10.1021/acs.organomet.6b00739
日期:2017.1.9
Cp*W(NO)(CH2CMe3)(eta(3)-CH2CHCHPh) (1) effects C(sp(3))-H activations of methane, ethane, propane, and n-butane exclusively at their terminal carbons and forms the corresponding Cp*W(NO)(alkyl)(eta(3)-CH2CHCHPh) complexes. It also activates (n-Bu)(2)O, 1-chloropropane, and Me4Si in a similar manner. Exposure of the Cp*W(NO)(alkyl)(eta(3)-CH2CHCHPh) complexes to carbon monoxide results in initial 1,1-CO insertion into the newly formed tungsten alkyl bonds and formation of the corresponding eta(1)-aryl complexes, some of which can be isolated. Additional functionalization of the C -H activation products occurs upon exposure to CO under more forcing conditions. Such treatment produces eta(2)-bound unsaturated-ketone complexes resulting from CO insertion into the W-alkyl sigma bonds followed by cross-coupling of the eta(1)-aryl and the eta(3)-allyl ligands and coordination of CO at the resulting vacant coordination site at tungsten. The unsaturated ketones can be released from the metal's coordination spheres either by photolysis of the complexes in MeCN or by further exposure of them to CO. All new compounds have been characterized by conventional spectroscopic and analytical methods, and. the solid-state molecular structures of six of them have been established by single-crystal X-ray crystallographic analyses.