50552-30-2Relevant academic research and scientific papers
Rhodium-Catalyzed Branched and Enantioselective Direct α-Allylic Alkylation of Simple Ketones with Alkynes
Ma, Mingliang,Xie, Liyu,Xing, Dong,Yang, Haijian
supporting information, (2020/03/10)
Herein, we report the first direct branched-selective α-allylic alkylation of simple ketones with alkynes under rhodium and secondary amine cooperative catalysis. Through a rhodium-hydride-catalyzed allylic substitution pathway, a series of valuable γ,δ-unsaturated ketones are obtained with excellent regioselectivity in an atom-economic and byproduct-free manner. With a chiral BIPHEP ligand, high enantioselectivity has been achieved for this transformation.
Gamma-alkenyl ketone and synthesis method thereof
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Paragraph 0100-0102, (2020/08/27)
The invention discloses gamma-alkenyl ketone and a preparation method thereof. Simple cyclic ketones or non-cyclic methyl ketones such as cyclopentanone and 1-phenyl-1-propyne are used as raw materials, and a target product is obtained with high yield, high regioselectivity and high enantioselectivity in the presence of an organic solvent, a catalyst, an additive and a ligand. The gamma-alkenyl ketone has the advantages of atom economy, high regioselectivity, high enantioselectivity and the like, and efficient conversion from cheap basic organic chemicals to high-added-value gamma-alkenyl ketone can be realized. The synthesized gamma-alkenyl ketone is a potential synthesis intermediate, and has potential application prospects in fine chemical synthesis and drug intermediate synthesis.
Regioselective Rhodium-Catalyzed Addition of β-Keto Esters, β-Keto Amides, and 1,3-Diketones to Internal Alkynes
Beck, Thorsten M.,Breit, Bernhard
supporting information, p. 5839 - 5844 (2016/12/18)
The first rhodium-catalyzed regioselective addition of 1,3-dicarbonyl compounds, including β-keto esters, β-keto amides, and 1,3-diketones, to internal alkynes furnishes branched allylic compounds. By applying RhI/DPEphos/TFA as the catalytic system, aliphatic as well as aromatic internal methyl-substituted alkynes act as suitable substrates to yield valuable branched α-allylated 1,3-dicarbonyl compounds regioselectively in good to excellent yields. A simple basic saponification–decarboxylation procedure provides access to valuable γ,δ-unsaturated ketones. The reaction shows a broad functional-group tolerance, and numerous structural variations on both reaction partners highlight the synthetic potential and flexibility of this method.
An Organocatalytic Cope Rearrangement
Kaldre, Dainis,Gleason, James L.
supporting information, p. 11557 - 11561 (2016/10/24)
The first example of an organocatalytic Cope rearrangement is reported. Acyclic and cyclic acyl hydrazides catalyze the rearrangement of 1,5-hexadiene-2-carboxaldehydes via iminium ion formation. A correlation between ring size and catalyst activity was observed for the cyclic hydrazides, with seven- and eight-membered-ring catalysts being the most active. Diazepane carboxylate 5 c (10 mol %) catalyzed the rearrangement of a range of dienes at room temperature in acetonitrile using triflic acid as a co-catalyst. Preliminary proof of principle for asymmetric catalysis was provided by rearrangement of 3,3-dimethyl-7-phenyl-1,5-heptadiene-2-carboxaldehyde in the presence of a novel 7-substituted diazepane carboxylate.
Rhodium-catalyzed chemo- and regioselective decarboxylative addition of β-ketoacids to alkynes
Li, Changkun,Grugel, Christian P.,Breit, Bernhard
supporting information, p. 5840 - 5843 (2016/05/19)
A highly efficient rhodium-catalyzed chemo- and regioselective addition of β-ketoacids to alkynes is reported. Applying a Rh(i)/(S,S)-DIOP catalyst system, γ,δ-unsaturated ketones were prepared with exclusively branched selectivity under mild conditions. This demonstrates that readily available alkynes can be an alternative entry to allyl electrophiles in transition-metal catalyzed allylic alkylation reactions.
Iridium-catalyzed regioselective decarboxylative allylation of β-ketoacids: Efficient construction of γ,δ-unsaturated ketones
Chen, Shu-Jie,Lu, Guo-Ping,Cai, Chun
supporting information, p. 11512 - 11514 (2016/01/15)
A highly regioselective protocol for the direct synthesis of γ,δ-unsaturated ketones from β-ketoacids and allylic alcohols was proposed and accomplished relying on the combination of [Ir(cod)Cl]2 and 10-camphorsulfonic acid via decarboxylative allylation.
Iridium-catalyzed enantioselective allyl-alkene coupling
Hamilton, James Y.,Sarlah, David,Carreira, Erick M.
supporting information, p. 3006 - 3009 (2014/03/21)
The direct Ir-catalyzed cross-coupling between branched, racemic allylic alcohols and simple olefins is described. This transformation is catalyzed by an Ir-(P,olefin) complex and proceeds with high site selectivity and excellent enantioselectivity. The m
Rhodium-catalyzed chemo- and regioselective decarboxylative addition of β-ketoacids to allenes: Efficient construction of tertiary and quaternary carbon centers
Li, Changkun,Breit, Bernhard
supporting information, p. 862 - 865 (2014/02/14)
A rhodium-catalyzed chemo- and regioselective intermolecular decarboxylative addition of β-ketoacids to terminal allenes is reported. Using a Rh(I)/DPPF system, tertiary and quaternary carbon centers were formed with exclusively branched selectivity under mild conditions. Preliminary mechanism studies support that the carbon-carbon bond formation precedes the decarboxylation and the reaction occurs in an outer-sphere mechanism.
Catalytic enantioselective allyl-allyl cross-coupling with a borylated allylboronate
Le, Hai,Kyne, Robert E.,Brozek, Laura A.,Morken, James P.
supporting information, p. 1432 - 1435 (2013/07/05)
Catalytic enantioselective allyl-allyl cross-coupling of a borylated allylboronate reagent gives versatile borylated chiral 1,5-hexadienes. These compounds may be manipulated in a number of useful ways to give functionalized chiral building blocks for asymmetric synthesis.
Chemo- and regioselectivity-tunable Pd-catalyzed allylic alkylation of imines
Chen, Jian-Ping,Peng, Qian,Lei, Bai-Lin,Hou, Xue-Long,Wu, Yun-Dong
supporting information; experimental part, p. 14180 - 14183 (2011/10/13)
α-Carbanions of cyclic and acyclic imines have been successfully applied as nucleophiles in the Pd-catalyzed allylic alkylation reaction. Tuning of chemo- and regioselectivity has been realized by using t-BuOK/THF and LDA/toluene to give branched and line
