39755-03-8Relevant articles and documents
Lewis acid mediated reactions of cyclopropyl aryl ketones with α-ketoesters: Facile preparation of 5,6-dihydropyran-2-ones
Yang, Yong-Hua,Shi, Min
, p. 10082 - 10085 (2005)
A new general method for the synthesis of 5,6-dihydropyran-2-ones from cyclopropyl aryl ketones (monoactivated cyclopropanes) and α-ketoesters in good to excellent yields has been developed. The process involves a cascade of reactions, including a nucleophilic ring-opening reaction of monoactivated cyclopropane by H2O, Lewis acid mediated transesterification, and an aldol type reaction.
A Sequential Activation of Alkyne and C-H Bonds for the Tandem Cyclization and Annulation of Alkynols and Maleimides through Cooperative Sc(III) and Cp*-Free Co(II) Catalysis
Gurram, Ravi Kumar,Rajesh, Manda,Reddy Singam, Maneesh Kumar,Nanubolu, Jagadeesh Babu,Reddy, Maddi Sridhar
, p. 5326 - 5330 (2020)
[4 + 2] oxidative Diels-Alder reaction of readily available alkynols with maleimide is achieved for the rapid access of pthalimide-fused multicyclic compounds. The reaction is proposed to go through a sequence of Sc(OTf)3-catalyzed electrophilic cyclization, ligand exchange with Cp*-free cobalt, and C-H activation followed by maleimide insertion.
P -TsOH promoted synthesis of benzo-fused O-heterocycles from alkynols via ring contraction and C-O scission strategy
Senadi, Gopal Chandru,Wang, Jeh-Jeng
, p. 3420 - 3425 (2018)
Here, we report the first divergent synthesis of benzo-fused O-heterocycles by p-toluene sulfonic acid promoted cascade reactions involving alkyne hydration, double cyclization, ring contraction and C-O bond cleavage from alkynols. The reaction mechanism
Cascade Reaction of Alkynols and 7-Oxabenzonorbornadienes Involving Transient Hemiketal Group Directed C-H Activation and Synergistic RhIII/ScIII Catalysis
Li, Deng Yuan,Jiang, Liang Liang,Chen, Shuang,Huang, Zheng Lu,Dang, Li,Wu, Xin Yan,Liu, Pei Nian
, p. 5134 - 5137 (2016)
As the first cascade C-H activation directed by a transient group, reaction of alkynols and 7-oxabenzonorbornadienes has been achieved via synergistic rhodium and scandium catalysis to afford spirocyclic dihydrobenzo[a]fluorenefurans. This transformation
Tunable Cascade Reactions of Alkynols with Alkynes under Combined Sc(OTf)3 and Rhodium Catalysis
Li, Deng Yuan,Chen, Hao Jie,Liu, Pei Nian
, p. 373 - 377 (2016)
Two tunable cascade reactions of alkynols and alkynes have been developed by combining Sc(OTf)3 and rhodium catalysis. In the absence of H2O, an endo-cycloisomerization/C-H activation cascade reaction provided 2,3-dihydronaphtho[1,2-b]furans in good to high yields. In the presence of H2O, the product of alkynol hydration underwent an addition/C-H activation cascade reaction with an alkyne, which led to the formation of 4,5-dihydro-3H-spiro[furan-2,1′-isochromene] derivatives in good yields under mild reaction conditions. Mechanistic studies of the cascade reactions indicated that the rate-determining step involves C-H bond cleavage and that the hydration of the alkynol plays a key role in switching between the two reaction pathways.
Biocatalytic reduction of α,β-unsaturated carboxylic acids to allylic alcohols
Aleku, Godwin A.,Leys, David,Roberts, George W.
, p. 3927 - 3939 (2020/07/09)
We have developed robust in vivo and in vitro biocatalytic systems that enable reduction of α,β-unsaturated carboxylic acids to allylic alcohols and their saturated analogues. These compounds are prevalent scaffolds in many industrial chemicals and pharmaceuticals. A substrate profiling study of a carboxylic acid reductase (CAR) investigating unexplored substrate space, such as benzo-fused (hetero)aromatic carboxylic acids and α,β-unsaturated carboxylic acids, revealed broad substrate tolerance and provided information on the reactivity patterns of these substrates. E. coli cells expressing a heterologous CAR were employed as a multi-step hydrogenation catalyst to convert a variety of α,β-unsaturated carboxylic acids to the corresponding saturated primary alcohols, affording up to >99percent conversion. This was supported by the broad substrate scope of E. coli endogenous alcohol dehydrogenase (ADH), as well as the unexpected CC bond reducing activity of E. coli cells. In addition, a broad range of benzofused (hetero)aromatic carboxylic acids were converted to the corresponding primary alcohols by the recombinant E. coli cells. An alternative one-pot in vitro two-enzyme system, consisting of CAR and glucose dehydrogenase (GDH), demonstrates promiscuous carbonyl reductase activity of GDH towards a wide range of unsaturated aldehydes. Hence, coupling CAR with a GDH-driven NADP(H) recycling system provides access to a variety of (hetero)aromatic primary alcohols and allylic alcohols from the parent carboxylates, in up to >99percent conversion. To demonstrate the applicability of these systems in preparative synthesis, we performed 100 mg scale biotransformations for the preparation of indole-3-aldehyde and 3-(naphthalen-1-yl)propan-1-ol using the whole-cell system, and cinnamyl alcohol using the in vitro system, affording up to 85percent isolated yield.
Sequential multicomponent catalytic synthesis of pyrrole-3-carboxaldehydes: Evaluation of antibacterial and antifungal activities along with docking studies
Choudhary, Sachin,Kant, Rajni,Kumar, Indresh,Mir, Nisar A.,Ramaraju, Panduga,Sankaranarayanan, Murugesan,Sharma, Preetika,Singh, Rajnish P.,Singh, Rajpal,Vanaparthi, Satheeshvarma
supporting information, p. 16329 - 16339 (2020/10/14)
A sequential multicomponent synthesis of highly substituted pyrrole-3-carboxaldehydes has been developed under metal-free conditions. This one-pot protocol involves proline-catalyzed direct chemoselective Mannich reaction-cyclization between 1,4-ketoaldehyde and in situ generated Ar/HetAr-imines followed by aerobic oxidative-aromatization at room temperature. A series of fully substituted pyrrole-3-carboxaldehydes and other diverse fused heterocycles have been synthesized. These compounds were tested for in vitro antibacterial and antifungal activities, and the selected ones display significant activity against the tested bacterial strains with a MIC value of 16 μg mL-1, which is close to that of the standard drug chloramphenicol. The bioactivity outcome was further analyzed using docking studies.
Photocatalysis with Quantum Dots and Visible Light: Selective and Efficient Oxidation of Alcohols to Carbonyl Compounds through a Radical Relay Process in Water
Zhao, Lei-Min,Meng, Qing-Yuan,Fan, Xiang-Bing,Ye, Chen,Li, Xu-Bing,Chen, Bin,Ramamurthy, Vaidhyanathan,Tung, Chen-Ho,Wu, Li-Zhu
supporting information, p. 3020 - 3024 (2017/03/13)
Selective oxidation of alcohols to aldehydes/ketones has been achieved with the help of 3-mercaptopropionic acid (MPA)-capped CdSe quantum dot (MPA-CdSe QD) and visible light. Visible-light-prompted electron-transfer reaction initiates the oxidation. The thiyl radical generated from the thiolate anion adsorbed on a CdSe QD plays a key role by abstracting the hydrogen atom from the C?H bond of the alcohol (R1CH(OH)R2). The reaction shows high efficiency, good functional group tolerance, and high site-selectivity in polyhydroxy compounds. The generality and selectivity reported here offer a new opportunity for further applications of QDs in organic transformations.
Method for synthesizing aromatic aldehyde, aromatic ketone and aromatic ester through catalytically oxidizing alkyl aromatic compound by iron
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Paragraph 0066; 0067, (2017/10/13)
The invention discloses a method for synthesizing aromatic aldehyde, aromatic ketone and aromatic ester through catalytically oxidizing an alkyl aromatic compound by iron, and belongs to the technical field of catalytic synthesis. According to the method, a low-cost and environment-friendly iron catalyst is used under a normal pressure; under the action of hydrogen and silicon reagents serving as an accelerant and an oxidant, a side chain of an aromatic hydrocarbon is oxidized into a carbonyl group for generating the corresponding aromatic aldehyde, aromatic ketone and aromatic ester. The method for preparing the aromatic aldehyde, the aromatic ketone and the aromatic ester through a catalytic oxidation reaction, which is provided by the invention, has numerous advantages that a catalyst, reaction raw materials, the oxidant and a silicon reagent are wide in sources and good in stability and is low-cost and environment-friendly; the alkyl aromatic compound is metered to participate in a reaction; the reaction condition is mild; the compatibility of functional groups is good; the scope of application is wide; the reaction selectivity is good; in an optimized reaction condition, the separation yield of a target product can be up to approximately 95 percent.
Accessing alternative reaction pathways of the intermolecular condensation between homo-propargyl alcohols and terminal alkynes through divergent gold catalysis
Smith, Courtney A.,Motika, Stephen E.,Wojtas, Lukasz,Shi, Xiaodong
, p. 2315 - 2318 (2017/02/23)
An intermolecular condensation of alkynols and terminal alkynes is reported. Using IPrAuNTf2, an efficient Au-catalyzed cyclization-alkynylation strategy furnishes (2-arylalkynyl) cyclic ethers in moderate to excellent yields (up to 94%). This strategy is extended to the synthesis of functionalized 2,3-dihydrooxepines via the sequential Au-catalyzed ring expansion of the cyclic ether substrates.
