582-62-7Relevant academic research and scientific papers
Nickel-Catalyzed Reductive Acylation of Carboxylic Acids with Alkyl Halides and N-Hydroxyphthalimide Esters Enabled by Electrochemical Process
Guo, Lin,Xia, Raymond Yang,Xia, Wujiong,Yang, Chao,Zhang, Haoxiang,Zhou, Xiao
supporting information, (2022/03/31)
A sustainable Ni-catalyzed reductive acylation reaction of carboxylic acids via an electrochemical pathway is presented, affording a variety of ketones as major products. The reaction proceeds at ambient temperature using unactivated alkyl halides and N-hydroxyphthalimide (NHP) esters as coupling partners, which exhibits several synthetic advantages, including mild conditions and convenience of amplification (58% yield for 6 mmol scale reaction). (Figure presented.).
KOtBu/DMSO Catalytic System for Isomerization of Allylic Alcohols to Ketones
Sai, Masahiro
, (2022/04/03)
The isomerization of allylic alcohols is an important reaction because it can afford carbonyl compounds in an atom-economical manner. Although base-catalyzed methods are more desirable than those using transition-metal catalysts from both the economic and environmental points of view, these methods have several drawbacks, such as narrow substrate scope and high catalyst loading. This paper reports the development of an efficient KOtBu/DMSO catalytic system suitable for the isomerization of a broad range of allylic alcohols with good yields, to which previously reported systems could not be applied. This catalytic system was successfully applied to a tandem allylic isomerization/electrophilic trapping reaction, thereby highlighting its synthetic utility.
o-Quinone methide with overcrowded olefin component as a dehydridation catalyst under aerobic photoirradiation conditions
Uraguchi, Daisuke,Kato, Kohsuke,Ooi, Takashi
, p. 2778 - 2783 (2021/03/14)
Ano-quinone methide (o-QM) featuring an overcrowded olefinic framework is introduced, which exhibits dehydridation activity owing to its enhanced zwitterionic character, particularly through photoexcitation. The characteristics of thiso-QM enable the operation of dehydridative catalysis in the oxidation of benzylic secondary alcohols under aerobic photoirradiation conditions. An experimental analysis and density functional theory calculations provide mechanistic insights; the ground-state zwitterionic intermediate abstracts a hydride and proton simultaneously, and the active oxygen species facilitate catalyst regeneration.
Highly Selective Hydrogenation of C═C Bonds Catalyzed by a Rhodium Hydride
Gu, Yiting,Lisnyak, Vladislav G.,Norton, Jack R.,Salahi, Farbod,Snyder, Scott A.,Zhou, Zhiyao
supporting information, p. 9657 - 9663 (2021/07/19)
Under mild conditions (room temperature, 80 psi of H2) Cp*Rh(2-(2-pyridyl)phenyl)H catalyzes the selective hydrogenation of the C═C bond in α,β-unsaturated carbonyl compounds, including natural product precursors with bulky substituents in the β position and substrates possessing an array of additional functional groups. It also catalyzes the hydrogenation of many isolated double bonds. Mechanistic studies reveal that no radical intermediates are involved, and the catalyst appears to be homogeneous, thereby affording important complementarity to existing protocols for similar hydrogenation processes.
Cobalt-Catalyzed Aerobic Oxidative Cleavage of Alkyl Aldehydes: Synthesis of Ketones, Esters, Amides, and α-Ketoamides
Li, Tingting,Hammond, Gerald B.,Xu, Bo
supporting information, p. 9737 - 9741 (2021/05/31)
A widely applicable approach was developed to synthesize ketones, esters, amides via the oxidative C?C bond cleavage of readily available alkyl aldehydes. Green and abundant molecular oxygen (O2) was used as the oxidant, and base metals (cobalt and copper) were used as the catalysts. This strategy can be extended to the one-pot synthesis of ketones from primary alcohols and α-ketoamides from aldehydes.
1,2-PHENYLENE BRIDGED 1-INDENYL-2-INDENYL METALLOCENE COMPLEXES FOR OLEFIN POLYMERISATION
-
Paragraph 0088-0089, (2019/08/12)
The invention relates to a metallocene complex according to formula (I), (I) wherein R1 and R2 are independently selected from H, an alkyl or an aryl group, wherein R3 is a C1 -C10 alkyl group, wherein R' is selected from H, an alkyl group, an aryl group and wherein different R' substituents can be connected to form a ring structure and wherein B is a 1,2 phenylene bridging moiety, which can be optionally substituted, wherein Mt is selected from Ti, Zr and Hf, X is an anionic ligand, z is the number of X groups and equals the valence of Mt minus 2. The invention also relates to a catalyst comprising the reaction product of the metallocene complex and a cocatalyst. Further the invention relates to a (co)polymerisation process of olefinic monomers.
Mild Cu-Catalyzed Oxidation of Benzylic Boronic Esters to Ketones
Grayson, James D.,Partridge, Benjamin M.
, p. 4296 - 4301 (2019/05/14)
The oxidation of benzylic boronic esters directly to the ketone is reported. This mild Cu-catalyzed method uses an ambient atmosphere of air as the terminal oxidant and is notably chemoselective. Oxidation of the C-B bond occurs selectively, even in the presence of unprotected alcohols. Initial investigation suggests the reaction proceeds through an alkylboron to Cu transmetalation, peroxide formation, and rearrangement to give the carbonyl.
Electrochemical C(sp 3)-H Fluorination
Baran, Phil S.,Chen, Longrui,Chen, Miao,Hoshikawa, Tamaki,Kawamata, Yu,Li, Chao,Mykhailiuk, Pavel,Nakamura, Hugh,Peters, Byron K.,Reisberg, Solomon H.,Shibuguchi, Tomoyuki,Takahira, Yusuke
supporting information, p. 1178 - 1182 (2019/06/08)
A simple and robust method for electrochemical alkyl C-H fluorination is presented. Using a simple nitrate additive, a widely available fluorine source (Selectfluor), and carbon-based electrodes, a wide variety of activated and unactivated C-H bonds are converted into their C-F congeners. The scalability of the reaction is also demonstrated with a 100 gram preparation of fluorovaline.
Palladium-Catalyzed Carbonylative Coupling of Aryl Iodides with Alkenylaluminum Reagents
Chen, Bo,Wu, Xiao-Feng
supporting information, p. 7624 - 7629 (2019/10/02)
A highly reactive catalytic system for the carbonylative coupling of aryl iodides with alkenylaluminum reagents has been developed. Various β-substituted γ,δ-unsaturated ketones were produced under mild conditions in good to excellent yields even under ppm level of palladium catalyst. Notably, this also represents the first example on carbonylative transformation of alkenylaluminum compounds. Additionally, by the addition of zinc salt, the selectivity of the product can be modified.
Arylation of Aldehydes to Directly Form Ketones via Tandem Nickel Catalysis
Lei, Chuanhu,Zhu, Daoyong,Tangcueco, Vicente Iii Tiu,Zhou, Jianrong Steve
supporting information, p. 5817 - 5822 (2019/08/26)
A nickel-catalyzed arylation of both aliphatic and aromatic aldehydes proceeds with air-stable (hetero)arylboronic acids, with an exceptionally wide substrate scope. The neutral condition tolerates acidic hydrogen and sensitive polar groups and also preserves α-stereocenters of some chiral aldehydes. Interestingly, this nickel(0) catalysis does not follow common 1,2-insertion of arylmetal species to aldehydes and β-hydrogen elimination.
