556-24-1Relevant articles and documents
Electrochemical esterification via oxidative coupling of aldehydes and alcohols
Smeyne, Dylan,Verboom, Katherine,Bryan, Maria,LoBue, James,Shaikh, Abid
supporting information, (2021/03/26)
An electrolytic method for the direct oxidative coupling of aldehydes with alcohols to produce esters is described. Our method involves anodic oxidation in presence of TBAF as supporting electrolyte in an undivided electrochemical cell equipped with graphite electrodes. This method successfully couples a wide range of alcohols to benzaldehydes with yields ranging from 70 to 90%. The protocol is easy to perform at a constant voltage conditions and offers a sustainable alternative over conventional methods.
Ambient Hydrogenation and Deuteration of Alkenes Using a Nanostructured Ni-Core–Shell Catalyst
Beller, Matthias,Feng, Lu,Gao, Jie,Jackstell, Ralf,Jagadeesh, Rajenahally V.,Liu, Yuefeng,Ma, Rui
supporting information, p. 18591 - 18598 (2021/06/28)
A general protocol for the selective hydrogenation and deuteration of a variety of alkenes is presented. Key to success for these reactions is the use of a specific nickel-graphitic shell-based core–shell-structured catalyst, which is conveniently prepared by impregnation and subsequent calcination of nickel nitrate on carbon at 450 °C under argon. Applying this nanostructured catalyst, both terminal and internal alkenes, which are of industrial and commercial importance, were selectively hydrogenated and deuterated at ambient conditions (room temperature, using 1 bar hydrogen or 1 bar deuterium), giving access to the corresponding alkanes and deuterium-labeled alkanes in good to excellent yields. The synthetic utility and practicability of this Ni-based hydrogenation protocol is demonstrated by gram-scale reactions as well as efficient catalyst recycling experiments.
Iron-catalysed 1,2-aryl migration of tertiary azides
Wei, Kaijie,Yang, Tonghao,Chen, Qing,Liang, Siyu,Yu, Wei
supporting information, p. 11685 - 11688 (2020/10/19)
1,2-Aryl migration of α,α-diaryl tertiary azides was achieved by using the catalytic system of FeCl2/N-heterocyclic carbene (NHC) SIPr·HCl. The reaction generated aniline products in good yields after one-pot reduction of the migration-resultant imines.
Selective hydrogenation of α,β-unsaturated carbonyl compounds on silica-supported copper nanoparticles
Mendes-Burak, Jorge,Ghaffari, Behnaz,Copéret, Christophe
supporting information, p. 179 - 181 (2019/01/04)
Silica-supported copper nanoparticles prepared via surface organometallic chemistry are highly efficient for the selective hydrogenation of various α,β-unsaturated carbonyl compounds yielding the corresponding saturated esters, ketones, and aldehydes in the absence of additives. High conversions and selectivities (>99%) are obtained for most substrates upon hydrogenation at 100-150 °C and under 25 bar of H2.
STABILIZATION OF ACTIVE METAL CATALYSTS AT METAL-ORGANIC FRAMEWORK NODES FOR HIGHLY EFFICIENT ORGANIC TRANSFORMATIONS
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Paragraph 0338, (2019/01/07)
Metal-organic framework (MOFs) compositions based on post?synthetic metalation of secondary building unit (SBU) terminal or bridging OH or OH2 groups with metal precursors or other post-synthetic manipulations are described. The MOFs provide a versatile family of recyclable and reusable single-site solid catalysts for catalyzing a variety of asymmetric organic transformations, including the regioselective boryiation and siiylation of benzyiic C—H bonds, the hydrogenation of aikenes, imines, carbonyls, nitroarenes, and heterocycles, hydroboration, hydrophosphination, and cyclization reactions. The solid catalysts can also be integrated into a flow reactor or a supercritical fluid reactor.
Development of efficient palladium catalysts for alkoxycarbonylation of alkenes
Liu, Jiawang,Dong, Kaiwu,Franke, Robert,Neumann, Helfried,Jackstell, Ralf,Beller, Matthias
supporting information, p. 12238 - 12241 (2018/11/21)
Herein, we report a general and efficient Pd-catalysed alkoxycarbonylation of sterically hindered and demanding olefins including a variety of tri-, tetra-substituted and 1,1-disubstituted alkenes. In the presence of 1,3-bis(tert-butyl(pyridin-2-yl)phosphanyl)propane L3 or 1,4-bis(tert-butyl(pyridin-2-yl)phosphanyl)butane L4 the desired esters are obtained in good yields and selectivities. Similar transformation is obtained using tertiary ether as showcased in the carbonylation of MTBE to the corresponding linear ester in high yield and selectivity.
PROCESS FOR THE PREPARATION OF ESTERS BY MEANS OF CARBONYLATION OF ETHERS
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Paragraph 0090; 0108-0110, (2018/04/02)
The invention relates to a process comprising the process steps of: a) initially charging an ether having from 3 to 30 carbon atoms;b) adding a phosphine ligand and a compound comprising Pd, or adding a comprising Pd and a phosphine ligand;c) feeding in CO;d) heating the reaction mixture, with conversion of the ether; wherein the phosphine ligand is a compound of formula (I) where m and n are each independently 0 or 1; R1, R2, R3, R4 are each independently selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C6-C20)-aryl, —(C3-C20)-heteroaryl; at least one of the R1, R2, R3, R4 radicals is a —(C3-C20)-heteroaryl radical; and R1, R2, R3, R4, if they are —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C6-C20)-aryl or —(C3-C20)-heteroaryl, may each independently be substituted by one or more substituents selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —O—(C1-C12)-alkyl, —O—(C1-C12)-alkyl-(C6-C20)-aryl, —O—(C3-C12)-cycloalkyl, —S—(C1-C12)-alkyl, —S—(C3-C12)-cycloalkyl, —COO—(C1-C12)-alkyl, —COO—(C3-C12)-cycloalkyl, —CONH—(C1-C12)-alkyl, —CONH—(C3-C12)-cycloalkyl, —CO—(C1-C12)-alkyl, —CO—(C3-C12)-cycloalkyl, —N—[(C1-C12)-alkyl]2, —(C6-C20)-aryl, —(C6-C20)-aryl-(C1-C12)-alkyl, —(C6-C20)-aryl-O—(C1-C12)-alkyl, —(C3-C20)-heteroaryl, —(C3-C20)heteroaryl-(C1-C12)-alkyl, —(C3-C20)-heteroaryl-O—(C1-C12)-alkyl, —COOH, —SO3H, —NH2, halogen; and wherein no alcohol is added to the reaction mixture.
PROCESS FOR THE ALKOXYCARBONYLATION OF ALCOHOLS
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Paragraph 0139; 0140, (2018/02/28)
The invention relates to a process comprising the following process steps: a) introducing a first alcohol, the first alcohol having 2 to 30 carbon atoms;b) adding a phosphine ligand and a compound which comprises Pd, or adding a complex comprising Pd and a phosphine ligand;c) adding a second alcohol;d) supplying CO;e) heating the reaction mixture, the first alcohol reacting with CO and the second alcohol to form an ester; where the phosphine ligand is a compound of formula (I) where m and n are each independently 0 or 1;R1, R2, R3, R4 are each independently selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C6-C20)-aryl, —(C3-C20)-heteroaryl;at least one of the R1, R2, R3, R4 radicals is a —(C3-C20)-heteroaryl radical;andR1, R2, R3, R4, if they are —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —(C6-C20)-aryl or —(C3-C20)-heteroaryl,may each independently be substituted by one or more substituents selected from —(C1-C12)-alkyl, —(C3-C12)-cycloalkyl, —(C3-C12)-heterocycloalkyl, —O—(C1-C12)-alkyl, —O—(C1-C12)-alkyl-(C6-C20)-aryl, —O—(C3-C12)-alkyl, —S—(C1-C12)-alkyl, —S—(C3-C12)-cycloalkyl, —COO—(C1-C12)-alkyl, —COO—(C3-C12)-cycloalkyl, —CONH—(C1-C12)-alkyl, —CONH—(C3-C12)-cycloalkyl, —CO—(C1-C12)-alkyl, —CO—(C3-C12)-cycloalkyl, —N—[(C1-C12)-alkyl]2, —(C6-C20)-aryl, —(C6-C20)-aryl-(C1-C12)-alkyl, —(C6-C20)-aryl-O—(C1-C12)-alkyl, —(C3-C20)-heteroaryl, —(C3-C20)-heteroaryl-(C1-C12)-alkyl, —(C3-C20)-heteroaryl-O—(C1-C12)-alkyl, —COON, —OH, —SO3H, —NH2, halogen.
Metal-Free Catalytic Reduction of α,β-Unsaturated Esters by 1,3,2-Diazaphospholene and Subsequent C-C Coupling with Nitriles
Chong, Che Chang,Rao, Bin,Kinjo, Rei
, p. 5814 - 5819 (2017/09/15)
1,3,2-Diazaphospholene 1 catalyzes the conjugate transfer hydrogenation as well as the 1,4-hydroboration of α,β-unsaturated esters. The initial step for both processes involves a 1,4-hydrophosphination of the α,β-unsaturated esters to afford a phosphinyl enol ether. Subsequent cleavage of the P-O bond in the phosphinyl enol ether by ammonia-borane (AB) generates an enol intermediate which tautomerizes to saturated esters, while the P-O bond cleavage by HBpin via a formal σ-bond metathesis affords boryl enolate intermediate. The latter could undergo a further coupling reaction with nitriles to form substituted amino diesters or 1,3-imino esters, depending on α,β-unsaturated ester substrates. These catalytic reactions can also be performed in a one-pot manner, illustrating a protocol for metal-free catalytic C-C bond construction.
Palladium-Catalyzed Carbonylation of sec- and tert-Alcohols
Dong, Kaiwu,Sang, Rui,Liu, Jie,Razzaq, Rauf,Franke, Robert,Jackstell, Ralf,Beller, Matthias
supporting information, p. 6203 - 6207 (2017/05/22)
A general palladium-catalyzed synthesis of linear esters directly from sec- and tert-alcohols is described. Compared to the classic Koch–Haaf reaction, which leads to branched products, this new transformation gives the corresponding linear esters in high yields and selectivity. Key for this protocol is the use of an advanced palladium catalyst system with L2 (pytbpx) as the ligand. A variety of aliphatic and benzylic alcohols can be directly used and the catalyst efficiency for the benchmark reaction is outstanding (turnover number up to 89 000).
