- Cobalt-Catalyzed Aerobic Oxidative Cleavage of Alkyl Aldehydes: Synthesis of Ketones, Esters, Amides, and α-Ketoamides
-
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.
- Li, Tingting,Hammond, Gerald B.,Xu, Bo
-
supporting information
p. 9737 - 9741
(2021/05/31)
-
- Homobenzylic Oxygenation Enabled by Dual Organic Photoredox and Cobalt Catalysis
-
Activation of aliphatic C(sp3)-H bonds in the presence of more activated benzylic C(sp3)-H bonds is often a nontrivial, if not impossible task. Herein we show that leveraging the reactivity of benzylic C(sp3)-H bonds to achieve reactivity at the homobenzylic position can be accomplished using dual organic photoredox/cobalt catalysis. Through a two-part catalytic system, alkyl arenes undergo dehydrogenation followed by an anti-Markovnikov Wacker-type oxidation to grant benzyl ketone products. This formal homobenzylic oxidation is accomplished with high atom economy without the use of directing groups, achieving valuable reactivity that traditionally would require multiple chemical transformations.
- McManus, Joshua B.,Griffin, Jeremy D.,White, Alexander R.,Nicewicz, David A.
-
supporting information
p. 10325 - 10330
(2020/07/27)
-
- Anti-Markovnikov Oxidation of β-Alkyl Styrenes with H2O as the Terminal Oxidant
-
Oxygenation of alkenes is one of the most straightforward routes for the construction of carbonyl compounds. Wacker oxidation provides a broadly useful strategy to convert the mineral oil into higher value-added carbonyl chemicals. However, the conventional Wacker chemistry remains problematic, such as the poor activity for internal alkenes, the lack of anti-Markovnikov regioselectivity, and the high cost and chemical waste resulted from noble metal catalysts and stoichiometric oxidant. Here, we describe an unprecedented dehydrogenative oxygenation of β-alkyl styrenes and their derivatives with water under external-oxidant-free conditions by utilizing the synergistic effect of photocatalysis and proton-reduction catalysis that can address these challenges. This dual catalytic system possesses the single anti-Markovnikov selectivity due to the property of the visible-light-induced alkene radical cation intermediate.
- Zhang, Guoting,Hu, Xia,Chiang, Chien-Wei,Yi, Hong,Pei, Pengkun,Singh, Atul K.,Lei, Aiwen
-
supporting information
p. 12037 - 12040
(2016/09/28)
-
- Direct Asymmetric Reductive Amination for the Synthesis of Chiral β-Arylamines
-
The highly efficient and direct asymmetric reductive amination of arylacetones catalyzed by an iridium complex for the preparation of enantiomerically pure β-arylamines is described. The monodentate phosphoramidite ligand exhibits superb reactivity (TONs of up to 20 000) and enantioselectivity (up to 99 % ee). Additives played important roles in this reductive coupling reaction. Asymmetric reductive coupling of a ketone and an amine is a straightforward and atom-economic approach for preparing optically enriched amines. The highly efficient and direct asymmetric reductive amination of arylacetones, catalyzed by an iridium complex, supplies enantiomerically pure β-arylamines. The new phosphoramidite ligands reported show superb reactivity and enantioselectivity in this reductive coupling. M.S.=molecular sieves, TFA=trifluoroacetic acid.
- Huang, Haizhou,Liu, Xiaoyan,Zhou, Le,Chang, Mingxin,Zhang, Xumu
-
supporting information
p. 5309 - 5312
(2016/04/26)
-
- DIALKYL(2-ALKOXY-6-AMINOPHENYL)PHOSPHINE, THE PREPARATION METHOD AND USE THEREOF
-
The present invention relates to the compound of dialkyl(2-alkoxy-6-aminophenyl)phosphine and the preparation method thereof and the application in the palladium catalyzed coupling reactions of aryl chloride and ketone. The dialkyl(2-alkoxy-6-aminophenyl)phosphine of the present invention could coordinate with the palladium catalyst to highly selectively activate the inert carbon-chlorine bond, and to catalyze direct arylation reaction in the α-position of ketones to produce corresponding coupling compounds. The preparation method of the present invention is a simple one-step method which produces the air-stable dialkyl(2-alkoxy-6-aminophenyl)phosphine. Compared with the synthetic routes of ligands to be used in the activation of carbon-chlorine bonds in the prior arts, the preparation method of the present invention has the advantages of short route and easy operation.
- -
-
Paragraph 0071; 0072; 0079; 0080
(2014/10/29)
-
- NITROGEN-CONTAINING CONDENSED HETEROCYCLIC COMPOUND
-
There are provided compounds represented by the following general formula (I) or pharmaceutically acceptable salts of thereof, which have a superior monoacylglycerol acyltransferase 2 inhibitory action: wherein Ring A represents a partially saturated heteroaryl group, an aryl group or a heteroaryl group, RB represents a C4-18 alkyl group, a C3-8 cycloalkyl group, a partially saturated aryl group, an aryl group, or the following formula (II): wherein V represents the formula -CR11R12-, -CO-, -CO-O-, or -CO-NH-, W represents a single bond or a C1-3 alkylene group, and Ring B represents a C3-8 cycloalkyl group, a C3-8 cycloalkenyl group, a partially saturated heteroaryl group, a saturated heterocyclyl group, an aryl group, or a heteroaryl group, Y represents a nitrogen atom or the formula N+(RF), RF represents a C1-4 alkyl group, and m and n, which may be the same or different, each represent an integer of 0 or 1.
- -
-
-
- Addressing challenges in palladium-catalyzed cross-couplings of aryl mesylates: Monoarylation of ketones and primary alkyl amines
-
Mor(DalPhos) for Me(sylates): Described are the first examples of ketone mono-α-arylation and primary aliphatic amine monoarylation employing aryl methanesulfonate coupling partners. A range of functionalized aryl mesylates were employed with dialkyl ketones, and also with primary and secondary amines as well as the otherwise challenging coupling partners acetone and methylamine. Ad=adamantyl. Copyright
- Alsabeh, Pamela G.,Stradiotto, Mark
-
supporting information
p. 7242 - 7246
(2013/07/26)
-
- Zheda-phos for general α-monoarylation of acetone with aryl chlorides
-
A new, readily available, and air-stable monophosphine ligand, i.e., Zheda-Phos, has been developed for the general and highly effective palladium-catalyzed monoarylation of acetone with aryl chlorides. The reaction rate is of first-order dependence with the aryl chloride. Copyright
- Li, Pengbin,Lue, Bo,Fu, Chunling,Ma, Shengming
-
supporting information
p. 1255 - 1259
(2013/06/27)
-
- Palladium-catalyzed mono-α-arylation of acetone with aryl halides and tosylates
-
We report the first example of selective Pd-catalyzed mono-α- arylation of acetone employing aryl chlorides, bromides, iodides, and tosylates. The use of appropriately designed P,N-ligands proved to be the key to controlling the reactivity and selectivity. The reaction affords good yields with substrates containing a range of functional groups at modest Pd loadings using Cs2CO3 as the base and employing acetone as both a reagent and the solvent.(Figure Presented)
- Hesp, Kevin D.,Lundgren, Rylan J.,Stradiotto, Mark
-
supporting information; experimental part
p. 5194 - 5197
(2011/06/10)
-
- SUBSTITUTED PYRAZOLES AS PPAR AGONISTS
-
A compound of formula (I) and pharmaceutically acceptable salts, solvates and hydrolysable esters thereof (I) wherein: p is O or 1; q is O or 1; R1 and R2 are independently H or C1-3 alkyl; R3 and R4 are independently H, C1-6 alkyl, -OC1-6 alkyl, halogen, OH, C2-6 alkenyl or CF3; R5 is H, C1-6 alkyl (optionally substituted by one or more halogens, -COphenyl, OC1-6 alkyl, phenyl morpholino or C2-6 alkenyl. R6 is C1-6 alkyl, halogen, -OCH2 phenyl, phenyl (optionally substituted by C1-3 alkiyl), morpholino, pyrrolidino, piperidino, thiophenyl, furanyl pyridinyl or -OC2-6 alkenyl. These compounds activate the alpha and gamma subtypes fo the hppar receptor and are useful e.g. in the treatment of diabetes, dyslipidemia or syndrome X.
- -
-
Page/Page column 115
(2010/02/12)
-
- An Effective System to Synthesize Arylacetones. Substrate-ionic Liquid-ultrasonic Irradiation
-
Manganese(III) acetate-promoted aromatic acetonylation has been accomplished with ultrasonic irradiation in ionic liquids, [N-n-pentyl-4- picolinium] [closo-CB11H12] (1), [OMIM] [BF4] and [BMIM] [PF6] in 62-93% yields, with excellent chemical selectivity.
- Yinghuai, Zhu,Bahnmueller, Stefan,Hosmane, Narayan S.,Maguire, John A.
-
p. 730 - 731
(2007/10/03)
-
- Behaviour of Arylazo tert-Butyl Sulfides with Ketone Enolates. Competition between SRN1 α-Arylation and Azocoupling Reactions.
-
(Z)-Arylazo tert-butyl sulfides 1a-i react, in DMSO and at room temperature, with potassium acetone enolate to give good yields of 1-aryl-2-propanones via spontaneous SRN1 dark reactions. α-Phenylation of pincolone and acetophenone enolates by 1a likewise occurs in excellent yields.In agreement with the involvement of an electron-transfer catalyzed chain process, the reaction of the 4-bromo derivative 1n with pinacolone enolate gives mainly the bis-substitution product 13.With azosulfides 1j-m the arylation pathway competes with a base-induced thiol elimination eventually leading, depending on the structure of the azosulfide, to indazoles 8 or 11 and/or to 2-oxopropanal arylhydrazones 9, 10 or 12.
- Dell'Erba, Carlo,Novi, Marino,Petrillo, Giovanni,Tavani, Cinzia
-
p. 325 - 334
(2007/10/02)
-