5331-64-6Relevant academic research and scientific papers
Total synthesis of (-)- and (+)-membrenone C.
Marshall, James A,Ellis, Keith C
, p. 1729 - 1732 (2003)
[reaction: see text] A synthesis of the polypropionate marine defense substance (+)-membrenone C and its enantiomer that starts from (S)-2-methyl-3-(tert-butyldimethylsilyloxy)propanal is described. Key steps include (1) additions of chiral allenylmetal reagents to effect both chain homologation and the concomitant introduction of four stereo centers, (2) a bis-intramolecular hydrosilylation-oxidation sequence to install beta-hydroxy ketone subunits, and (3) a bis-intramolecular aldol reaction to construct the two dihydropyrone termini.
Synthesis of Highly Substituted Biaryls by the Construction of a Benzene Ring via in Situ Formed Acetals
Balamurugan, Rengarajan,Manojveer, Seetharaman,Tarigopula, Chandrahas
, p. 11871 - 11883 (2021/09/13)
Herein, we present an interesting method for the construction of a benzene ring using propargylic alcohols and 1,3-dicarbonyls, which involves three new C-C bond formations via cascade alkylation, formylation, annulation, and aromatization to make substituted biaryls. This one-pot Br?nsted acid-promoted protocol utilizes the unique reactivity of the acetal formed under the reaction conditions. Alkynyl methyl ketones could be employed instead of 1,3-dicarbonyls as they are converted to 1,3-dicarbonyls by hydration under the reaction conditions.
Method of preparing 1,3-diketone compound by acetyenic ketone
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Paragraph 0126-0131, (2019/06/12)
The invention relates to a preparation method of preparing a 1,3-diketone compound by acetyenic ketone. The preparation method comprises the following steps: S1, putting alpha-alkynyl ketone compound,water, gold salt and silver salt in a reaction solvent to obtain a precursor mixture, wherein the molar ratio of the alpha-alkynyl ketone compound, water, gold salt and silver salt is 1: (1-50): (0.001-0.10): (0.002-0.15); and S2, putting the precursor mixture obtained in the S1 to react at a reaction temperature of 0-50 DEG C to obtain the 1,3-diketone compound, wherein the reaction time is 5 min to 48 h. The method is simple in reaction condition, free of acid or alkaline additives and high in yield, and can be applied to modern production on a large scale.
Novel Bifunctionalization of Activated Methylene: Base-Promoted Trifluoromethylthiolation of β-Diketones with Trifluoromethanesulfinyl Chloride
Sun, Dong-Wei,Jiang, Min,Liu, Jin-Tao
supporting information, p. 10797 - 10802 (2019/07/03)
A novel bifunctionalization of activated methylene was achieved successfully through the base-promoted trifluoromethylthiolation of β-diketones or β-ketoesters with trifluoromethanesulfinyl chloride. A series of α-trifluoromethylthiolated α-chloro-β-diketones and α-chloro-β-ketoesters were obtained in moderate to good yields under mild conditions. When β-diketones containing a phenyl group with a hydroxyl or amino substituent at the ortho position were used as substrates, intramolecular trifluoromethylthiolation/cyclization reaction took place to give the corresponding cyclic products. Furthermore, the protocol could be extended to perfluoroalkylthiolation with the sodium perfluoroalkanesulfinate/POCl3 system. On the basis of experimental results, plausible mechanisms are proposed.
Structure-dependent selective O- or C-trifluoroethylation of 1,3-dicarbonyls by mesityl(2,2,2-trifluoroethyl)iodonium triflate
Zhao, Cheng-Long,Yang, Jing,Han, Zhou-Zhou,Zhang, Cheng-Pan
supporting information, p. 23 - 30 (2017/10/30)
Reaction of [ArICH2CF3][OTf] with structurally diversified 1,3-dicarbonyls and an appropriate base at room temperature gave O-trifluoroethylated products, C-trifluoroethylated products, or a mixture of O- and C-trifluoroethylated products in good yields. The product type was dramatically dependent upon the structure of the starting 1,3-dicarbonyls in this reaction. The cyclic 1,3-diketones exclusively afforded the O-trifluoroethylated products, whereas the acyclic 1,3-diketones, β-keto esters, and malonates selectively or specifically formed the C-trifluoroethylated products. Li2CO3 facilitated the C-trifluoroethylation of acyclic 1,3-diketones and β-keto esters. The reaction proceeded under mild conditions, without pre-activation of 1,3-dicarbonyls and use of strong base, and demonstrated a catalyst-free structure-dependent regioselective trifluoroethylation of 1,3-dicarbonyls by mesityl(2,2,2-trifluoroethyl)iodonium triflate.
Direct synthesis of 1,3-dicarbonyl compounds via radical coupling of aldehydes with ketones under metal-free conditions
Shen, Xuqian,Borah, Arun Jyoti,Cao, Xihan,Pan, Weixiang,Yan, Guobing,Wu, Xiangmei
supporting information, p. 6484 - 6487 (2015/11/16)
An efficient approach for the synthesis of 1,3-diketones from aldehydes and ketones has been developed using Bu4NI (TBAI) as the catalyst. In the presence of DTBP-TBHP/p-TsOH, aldehydes undergo radical coupling with ketones to provide the desired products in moderate to high yields at 120 °C. Although various substituents on the aromatic ring of aldehydes are well tolerable under the standard reaction conditions, the protocol is limited by the scope of ketones. The method exhibits advantages in terms of the easy access of the starting materials, operational simplicity, functional group tolerance, and the absence of metal catalyst.
Selective oxidation of benzylic, allylic and propargylic alcohols using dirhodium(II) tetraamidinate as catalyst and aqueous tert-butyl hydroperoxide as oxidant
Wusiman, Abudureheman,Lu, Chong-Dao
, p. 254 - 258 (2015/03/30)
We show that the dirhodium(II) tetraamidinate complex Rh2(Msip)4 efficiently catalyzes the oxidation of activated secondary alcohols at only 0.1 mol% loading. In this approach, we oxidized various benzylic, allylic and propargylic alcohols to the corresponding carbonyl compounds under mild aqueous conditions using the inexpensive oxidant T-HYDRO (70 wt% aqueous tert-butyl hydroperoxide).
Palladium-catalysed carbonylative α-arylation of acetone and acetophenones to 1,3-diketones
Schranck, Johannes,Tlili, Anis,Alsabeh, Pamela G.,Neumann, Helfried,Stradiotto, Mark,Beller, Matthias
supporting information, p. 12624 - 12628 (2013/10/01)
Three COmponent α-arylation: A carbonylative ketone α-arylation process employing acetone for the first time, as well as acetophenones, is described (see scheme). The reaction tolerates a range of (hetero)aryl iodides and several functionalised aryl ketone coupling partners. Only low pressures of molecular CO are applied and no additional solvent is necessary. Copyright
A facile synthesis of α-fluoro ketones catalyzed by [Cp*IrCl2]2
Ahlsten, Nanna,Bartoszewicz, Agnieszka,Agrawal, Santosh,Martin-Matute, Belen
, p. 2600 - 2608 (2011/10/02)
Allylic alcohols are isomerized into enolates (enols) by [Cp*IrCl2]2. The enolates react with Selectfluor present in the reaction media. This method produces α-fluoro ketones as single constitutional isomers in high yields. Georg Thieme Verlag Stuttgart. New York.
Enantioselective synthesis of optically pure β-amino ketones and γ-aryl amines by Rh-catalyzed asymmetric hydrogenation
Geng, Huiling,Huang, Kexuan,Sun, Tian,Li, Wei,Zhang, Xiaowei,Zhou, Le,Wu, Wenjun,Zhang, Xumu
supporting information; experimental part, p. 332 - 334 (2011/03/19)
A series of optically pure β-amino ketones have been synthesized in high enantioselectivities (ee > 99%) by Rh-DuanPhos-catalyzed asymmetric hydrogenation of readily prepared β-keto enamides. Further reduction of these β-amino ketones with hydrogen and Pd/C leads to the formation of a variety of protected enantiomerically pure γ-aryl amines (ee > 99%), which are key building blocks in many bioactive molecules.
