13033-04-0Relevant academic research and scientific papers
Iron-catalysed alkylation of 2-methyl and 4-methyl azaarenes with alcoholsviaC-H bond activation
Banerjee, Debasis,Bera, Sourajit,Kabadwal, Lalit Mohan
supporting information, p. 4777 - 4780 (2020/05/13)
The first Fe-catalysed alkylation of 2-methyl and 4-methyl-azaarenes with a series of alkyl and hetero-aryl alcohols is reported (>39 examples and up to 95% yield). Multi-functionalisation of pyrazines and synthesis of anti-malarial drug (±) Angustureine significantly broaden the scope of this methodology. Preliminary mechanistic investigation, deuterium labeling and kinetic experiments including trapping of the enamine intermediate1a'are of special importance.
Iridium-Catalyzed C-Alkylation of Methyl Group on N-Heteroaromatic Compounds using Alcohols
Onoda, Mitsuki,Fujita, Ken-Ichi
supporting information, p. 7295 - 7299 (2020/10/02)
In this study, we developed a catalytic system for the C-alkylation of a methyl group on N-heteroaromatic compounds, including pyridine, pyrimidine, pyrazine, quinoline, quinoxaline, and isoquinoline, using alcohols based on a hydrogen-borrowing process with [Cp*IrCl2]2 (Cp*: η5-pentamethylcyclopentadienyl) combined with potassium t-butoxide and 18-crown-6-ether as the catalyst precursor.
Nickel-catalysed alkylation of C(sp3)-H bonds with alcohols: direct access to functionalised N-heteroaromatics
Vellakkaran, Mari,Das, Jagadish,Bera, Sourajit,Banerjee, Debasis
supporting information, p. 12369 - 12372 (2018/11/20)
The first base-metal catalysed coupling of primary alcohols with methyl-N-heteroaromatics is reported. The use of an earth abundant and nonprecious NiBr2/L1 system enables access to a series of C(sp3)-alkylated N-heteroaromatics. Mechanistic studies have established the participation of a hydrogen-borrowing strategy for α-alkylation.
Chromium-Catalyzed Cross-Coupling Reactions of Alkylmagnesium Reagents with Halo-Quinolines and Activated Aryl Chlorides
Bellan, Andreas B.,Kuzmina, Olesya M.,Vetsova, Violeta A.,Knochel, Paul
, p. 188 - 194 (2016/12/24)
An efficient protocol for chromium(III)-catalyzed C(sp2)-C(sp3) cross-coupling is reported. The alkylations of halo-quinoline and phenacyl derivatives proceed at room temperature within minutes using the tetrahydrofuran-soluble chrom
The copper-catalysed Suzuki-Miyaura coupling of alkylboron reagents: disproportionation of anionic (alkyl)(alkoxy)borates to anionic dialkylborates prior to transmetalation
Basnet, Prakash,Thapa, Surendra,Dickie, Diane A.,Giri, Ramesh
supporting information, p. 11072 - 11075 (2016/09/19)
We report the first example of CuI-catalysed coupling of alkylboron reagents with aryl and heteroaryl iodides that affords products in good to excellent yields. Preliminary mechanistic studies with alkylborates indicate that the anionic (alkoxy)(alkyl)borates, generated from alkyllithium and alkoxyboron reagents, undergo disproportionation to anionic dialkylborates and that both anionic alkylborates are active for transmetalation to a CuI-catalyst. Results from a radical clock experiment and the Hammett plot imply that the reaction likely proceeds via a non-radical pathway.
Alcohols as alkylating agents in heteroarene C-H functionalization
Jin, Jian,MacMillan, David W. C.
, p. 87 - 90 (2015/09/15)
Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage. One of the core principles underlying DNA biosynthesis is the radical-mediated elimination of H2O to deoxygenate ribonucleotides, an example of 'spin-centre shift', during which an alcohol C-O bond is cleaved, resulting in a carbon-centred radical intermediate. Although spin-centre shift is a well-understood biochemical process, it is underused by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylation reactions using alcohols as radical precursors. Because conventional radical-based alkylation methods require the use of stoichiometric oxidants, increased temperatures or peroxides, a mild protocol using simple and abundant alkylating agents would have considerable use in the synthesis of diversely functionalized pharmacophores. Here we describe the development of a dual catalytic alkylation of heteroarenes, using alcohols as mild alkylating reagents. This method represents the first, to our knowledge, broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer catalysis. The value of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone.
Metal-Free Oxidative Decarbonylative Coupling of Aliphatic Aldehydes with Azaarenes: Successful Minisci-Type Alkylation of Various Heterocycles
Tang, Ren-Jin,Kang, Lei,Yang, Luo
supporting information, p. 2055 - 2060 (2015/06/23)
A metal-free oxidative decarbonylative coupling of aliphatic aldehydes with various electron-deficient heterocycles has been developed. This reaction is supposed to be realized via a Minisci-type mechanism, based on the substrate scope, regioselectivity and radical trapping experiments. The ready availability of aliphatic aldehydes, metal-free conditions and broad substrate scope should make this method attractive for the late-stage alkylation of bioactive heterocycles.
