Lanthanide/B(C₆F₅)₃-Promoted Hydroboration Reduction of Indoles and Quinolines with Pinacolborane

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(2), P. 887 - 897

Published: Jan. 5, 2024

We have developed a lanthanide/B(C6F5)3-promoted hydroboration reduction of indoles and quinolines with pinacolborane (HBpin). This reaction provides streamlined access to range nitrogen-containing compounds in moderate excellent yields. Large-scale synthesis further transformations bioactive indicate that the method has potential practical applications. Preliminary mechanistic studies suggest amine additives promote formation indole-borane intermediates, proceeds via intermediates HBpin situ-formed BH3 species, followed by protodeborylation process.

Language: Английский

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Masters of Mediation: MN(SiMe₃)₂ in Functionalization of C(sp³)−H Latent Nucleophiles

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(29)

Published: March 18, 2024

Abstract Organoalkali compounds have undergone a far‐reaching transformation being coupling partner to mediator in unusual organic conversions which finds its spot the field of sustainable synthesis. Transition‐metal catalysis has always been priority C( sp 3 )−H bond functionalization, however alternatively, recent times this seriously challenged by earth‐abundant alkali metals and their complexes arriving at new organometallic reagents. In line, importance MN(SiMe ) 2 (M=Li, Na, K & Cs) reagent revived functionalization over years synthesis is showcased minireview. with higher reactivity, enhanced stability, bespoke cation‐π interaction shown eye‐opening mediated processes such as )−C( cross‐coupling, radical‐radical aminobenzylation, annulation, aroylation, other transformations utilize readily available petrochemical feedstocks. This article also emphasizes reactivity unreactive robust C−X (X=O, N, F, C) cleavage reactions that occurred alongside functionalization. Overall, review encourages community exploit untapped potential inspires them take up subject even greater heights.

Language: Английский

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Synthesis of Tri‐ and Tetrasubstituted Alkenyl Boronates from Alkynes

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(30)

Published: July 8, 2022

Abstract The synthesis of organoboron compounds have attracted the attention synthetic community. In particular, molecules with C(sp 2 )‐B bonds enable transformation to new C−C or C‐heteroatom by well‐established methodologies. Alkenyl boronates possibility for further conversion boron moiety functionalization double bond. This review gives an overview on recent methodologies selective preparation challenging highly substituted alkenyl from alkynes.

Language: Английский

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^tBuOLi-Promoted Hydroboration of Esters and Epoxides

ACS Omega, Journal Year: 2022, Volume and Issue: 7(22), P. 18876 - 18886

Published: May 25, 2022

Commercially available and inexpensive lithium tert-butoxide ( t BuOLi) acts as a good precatalyst for the hydroboration of esters, lactones, epoxides using pinacolborane borylation agent. Functional groups such cyano-, nitro-, amino-, vinyl, alkynyl are unaffected under presented process, representing high chemoselectivity. This transformation has also been effectively applied to synthesis key intermediates Erlotinib Cinacalcet. Preliminary investigations mechanism show that proceeds through in situ formed BH3 species.

Language: Английский

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CeO₂‐Nanorods‐Catalyzed Protoboration of Alkenes and Alkynes with Bis(pinacolato)diboron

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(4), P. 584 - 593

Published: Feb. 7, 2023

Abstract The protoboration of alkenes and alkynes with B 2 pin (pin=OCMe CMe O) using a heterogeneous CeO nanorods catalyst has been developed to afford the corresponding alkyl vinyl boronate esters in 41–99% yield under mild reaction conditions. A series aromatic aliphatic synthetically important functional groups were well tolerated. In both systems, could be reused for up six runs without significant loss activity. Stoichiometric reactions revealed that may proceed through situ formed catalytically active boryl species. magnified image

Language: Английский

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Organocatalytic hydroboration of olefins in pyrrolidinium ionic liquids

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(9), P. 3715 - 3722

Published: Jan. 1, 2023

ILs organocatalyzed regioselective hydroboration of alkenes with HBpin provides anti-Markovnikov adducts high yields and selectivity. The system allows catalyst recycling up to 30 runs. Transformations alkylboronic esters are also included.

Language: Английский

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Cobalt-Catalyzed Borylative Reduction of Azobenzenes to Hydrazobenzenes via a Diborylated-Hydrazine Intermediate

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(13), P. 9265 - 9274

Published: June 20, 2024

Cobalt-catalyzed borylative reduction of azobenzenes using pinacolborane is developed. The simple cobalt chloride catalyst and reaction conditions make this protocol attractive for hydrazobenzene synthesis. This shows good functional group compatibility can be readily scaled up to the gram scale. Preliminary mechanistic studies clarified proton source hydrazine products. cobalt-catalyzed azobenzene provides a practical prepare synthetically useful diborylated hydrazines.

Language: Английский

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Hydroboration of alkynes initiated by sodium triethylborohydride

Polyhedron, Journal Year: 2022, Volume and Issue: 223, P. 115961 - 115961

Published: June 11, 2022

Sodium triethylborohydride, a popular hydride transferring reagent, is commonly used as an activating agent for hydroboration catalysts based on the first-row transition metal complexes. It has been found that NaHBEt3 can be selective catalyst of terminal alkynes with pinacolborane. Hydroboration aromatic and aliphatic in presence 10 mol% proceeded highly manner to give (E)-vinylboronate esters high yields, whereas ethynylsilanes seem less reactive this process. Internal also transformed into corresponding vinylboronate esters, however, process require prolonged reaction times compared their counterparts.

Language: Английский

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A simple synthesis of surfactant-free polycrystalline CuO nanoparticles supported on carbon nanofibers for regioselective hydroboration of alkynes

RSC Advances, Journal Year: 2022, Volume and Issue: 12(38), P. 24998 - 25005

Published: Jan. 1, 2022

Copper oxide nanoparticles (CuO NPs) with a clean surface supported on carbon nanofibers (CNFs) in one-pot were prepared by simple solid-state grinding and aging followed thermal treatment, yielding CuO high (23.8 wt%) uniform loading the absence of surfactants solvent. The NPs CNFs (CuO/CNF) showed excellent catalytic activity transforming wide variety alkynes into alkenyl boronates using B2Pin2 as boron source ligand additives regioselectivity under mild conditions. Moreover, present CuO/CNF catalyst was recyclable possesses chemoselectivity. developed green synthetic approach is expected to offer exciting opportunities for designing monometallic or bimetallic nanoparticle catalysts different supports applied heterogeneous catalysis.

Language: Английский

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Research Progress on the Synthesis of Nitrogen-Containing Compounds with Cyanamide as a Building Block

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(2), P. 436 - 436

Published: Jan. 1, 2023

Nitrogen-containing compounds are widely found in many natural products and have a wide range of pharmacological physiological activities.Furthermore, they comprehensive applications medicine pesticide fields, industry multi-functional materials.Great advances the synthesis these been sprung up, diversity synthetic methods them via cyanamide (NH2-CN) as raw material were exploited recent years.The research progress on nitrogen-containing through building block is introduced comprehensively.Moreover, their characteristics, rules, advantages disadvantages summarized discussed for development new methodologies reactions compounds.

Language: Английский

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