Browse
Submit Data
Databases
API
Help

Dataset Information

16 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Copper(ii) ketimides in sp³ C-H amination.

ABSTRACT: Commercially available benzophenone imine (HN[double bond, length as m-dash]CPh₂) reacts with β-diketiminato copper(ii) tert-butoxide complexes [Cu^II]-O ^t Bu to form isolable copper(ii) ketimides [Cu^II]-N[double bond, length as m-dash]CPh₂. Structural characterization of the three coordinate copper(ii) ketimide [Me₃NN]Cu-N[double bond, length as m-dash]CPh₂ reveals a short Cu-N_ketimide distance (1.700(2) Å) with a nearly linear Cu-N-C linkage (178.9(2)°). Copper(ii) ketimides [Cu^II]-N[double bond, length as m-dash]CPh₂ readily capture alkyl radicals R˙ (PhCH(˙)Me and Cy˙) to form the corresponding R-N[double bond, length as m-dash]CPh₂ products in a process that competes with N-N coupling of copper(ii) ketimides [Cu^II]-N[double bond, length as m-dash]CPh₂ to form the azine Ph₂C[double bond, length as m-dash]N-N[double bond, length as m-dash]CPh₂. Copper(ii) ketimides [Cu^II]-N[double bond, length as m-dash]CAr₂ serve as intermediates in catalytic sp³ C-H amination of substrates R-H with ketimines HN[double bond, length as m-dash]CAr₂ and ^t BuOO ^t Bu as oxidant to form N-alkyl ketimines R-N[double bond, length as m-dash]CAr₂. This protocol enables the use of unactivated sp³ C-H bonds to give R-N[double bond, length as m-dash]CAr₂ products easily converted to primary amines R-NH₂ via simple acidic deprotection.

SUBMITTER: Jayasooriya IU

PROVIDER: S-EPMC8654034 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Photo-induced copper-catalyzed alkynylation and amination of remote unactivated C(sp3)-H bonds.

Project description:A method for remote radical C-H alkynylation and amination of diverse aliphatic alcohols has been developed. The reaction features a copper nucleophile complex formed in situ as a photocatalyst, which reduces the silicon-tethered aliphatic iodide to an alkyl radical to initiate 1,n-hydrogen atom transfer. Unactivated secondary and tertiary C-H bonds at β, γ, and δ positions can be functionalized in a predictable manner.

| S-EPMC8179574 | biostudies-literature

Copper-catalyzed dehydrogenative γ-C(sp3)-H amination of saturated ketones for synthesis of polysubstituted anilines.

Project description:Metal-catalyzed β-C-H functionalization of saturated carbonyls via dehydrogenative desaturation proved to be a powerful tool for simplifying synthesis of valuable β-substituted carbonyls. Here, we report a copper-catalyzed dehydrogenative γ-C(sp3)-H amination of saturated ketones that initiates the three-component coupling of saturated ketones, amines and N-substituted maleimides to construct polysubstituted anilines. The protocol presented herein enables both linear and α-branched butanones to couple a wide spectrum of amines and various N-substituted maleimides to produce diverse tetra- or penta-substituted anilines in fair-to-excellent yields with good functional group tolerance. The mechanism studies support that this ketone dehydrogenative γ-C(sp3)-H amination was triggered by the ketone α,β-dehydrogenation desaturation that activates the adjacent γ-C(sp3)-H bond towards functionalization. This α,β-dehydrogenation desaturation-triggered cascade sequence opens up a new avenue to the remote C(sp3)-H functionalization of saturated ketones and has the potential to enable the rapid syntheses of complex compounds from simple starting materials.

| S-EPMC6695438 | biostudies-literature

Electrochemical Dehydrogenative C(sp2 )-H Amination.

Project description:A transition-metal-free direct electrolytic C-H amination involving an electrochemically generated nitrenium ion intermediate has been developed. The electrosynthesis takes place in the absence of any organoiodine catalysts and is enabled by an in situ generated electrolyte. A novel, efficient intramolecular and intermolecular C-H amination has been demonstrated using a simple reaction setup.

| S-EPMC8251997 | biostudies-literature

Intramolecular 1,5-C(sp3)-H Radical Amination via Co(II)-Based Metalloradical Catalysis for Five-Membered Cyclic Sulfamides.

Project description:Co(II)-based metalloradical catalysis (MRC) proves effective for intramolecular 1,5-C-H amination of sulfamoyl azides under neutral and nonoxidative conditions, providing a straightforward approach to access strained 5-membered cyclic sulfamides with nitrogen gas as the only byproduct. The metalloradical amination system is applicable to different types of C(sp3)-H bonds and has a high degree of functional group tolerance. Additional features of the Co(II)-catalyzed 1,5-C-H amination include excellent chemoselectivity toward allylic and propargylic C-H bonds. The unique reactivity and selectivity profile of the Co(II)-catalyzed 1,5-C-H amination is attributed to the underlying radical mechanism of MRC.

| S-EPMC5271564 | biostudies-literature

A highly site-selective radical sp3 C-H amination of azaheterocycles.

Project description:This report describes the development of a novel C-H amination strategy using both a Cu(ii) Lewis acid and an organic hydrogen atom transfer catalyst to activate benzylic C-H bonds adjacent to aromatic N-heterocycles. This simple methodology demonstrates very high selectivity towards azaheterocycles without using exogenous directing groups and affords excellent site selectivity in substrates with more than one reactive position. A wide range of heterocyclic structures not compatible with previously reported catalytic systems have proven to be amenable to this approach. Mechanistic investigations strongly support a radical-mediated H-atom abstraction, which explains the observed contrast to known closed-shell Lewis acid catalyzed processes.

| S-EPMC6115697 | biostudies-literature

Silver Catalyzed Site-Selective C(sp3)-H Bond Amination of Secondary over Primary C(sp3)-H Bonds.

Project description:Sulfamates are widespread in numerous pharmacologically active molecules. In this paper, Silver/Bathophenanthroline catalyzed the intramolecular selective amination of primary C(sp3)-H bonds and secondary C(sp3)-H bonds of sulfamate esters, to produce cyclic sulfamates in good yields and with a high site-selectivity. DFT calculations revealed that the interaction between sulfamates and L10 makes the molecule more firmly attached to the catalyst, benefiting the catalysis reaction. The in vitro anticancer activity of the final products was evaluated in MCF-7 breast cancer cells.

| S-EPMC9571442 | biostudies-literature

Enantioselective Copper-Catalyzed sp2/sp3 Diborylation of 1-Chloro-1-Trifluoromethylalkenes.

Project description:Fluorine-containing organoboron compounds have emerged as novel building blocks in chemical synthesis; among them, fluorinated sp2/sp3 diborylated compounds are particularly appealing, since they might undergo chemoselective and diversified transformations of different C-B bonds with fluorinated functionality, thus bringing versatility and complexity to the eventual products. However, expedient, synthetic strategies for the construction of such fluorinated diborylative compounds are very sparse. Herein, we disclose enantioselective Cu-catalyzed sp2/sp3 diborylations of 1-chloro-1-trifluoromethylalkenes, leading to diborylated compounds bearing a gem-difluoroalkenyl moiety; most intriguingly, the new formed C-B bonds include one stereoselective and optically pure Csp3-B bond. Further transformations on the eventual products demonstrated the values of our presented strategy.

| S-EPMC9413839 | biostudies-literature

Intramolecular cascade annulation triggered by rhodium(III)-catalyzed sequential C(sp2)-H activation and C(sp3)-H amination.

Project description:A rhodium(III)-catalyzed intramolecular oxidative annulation of O-substituted N-hydroxyacrylamides for the construction of indolizinones via sequential C(sp2)-H activation and C(sp3)-H amination has been developed. This approach shows excellent functional-group tolerance. The synthesized scaffold forms the core of many natural products with pharmacological relevance.

| S-EPMC6404421 | biostudies-literature

Enzymatic C(sp3)-H Amination: P450-Catalyzed Conversion of Carbonazidates into Oxazolidinones.

Project description:Cytochrome P450 enzymes can effectively promote the activation and cyclization of carbonazidate substrates to yield oxazolidinones via an intramolecular nitrene C-H insertion reaction. Investigation of the substrate scope shows that while benzylic/allylic C-H bonds are most readily aminated by these biocatalysts, stronger, secondary C-H bonds are also accessible to functionalization. Leveraging this "non-native" reactivity and assisted by fingerprint-based predictions, improved active-site variants of the bacterial P450 CYP102A1 could be identified to mediate the aminofunctionalization of two terpene natural products with high regio- and stereoselectivity. Mechanistic studies and KIE experiments show that the C-H activation step in these reactions is rate-limiting and proceeds in a stepwise manner, namely, via hydrogen atom abstraction followed by radical recombination. This study expands the reactivity scope of P450-based catalysts in the context of nitrene transfer transformations and provides first-time insights into the mechanism of P450-catalyzed C-H amination reactions.

| S-EPMC4416466 | biostudies-literature

A General Method for Aminoquinoline-Directed, Copper-Catalyzed sp(2) C-H Bond Amination.

Project description:An operationally simple and general method for copper-catalyzed, aminoquinoline-assisted amination of ?-C(sp(2))-H bonds of benzoic acid derivatives is reported. The reaction employs Cu(OAc)2 or (CuOH)2CO3 catalysts, an amine coupling partner, and oxygen from air as a terminal oxidant. Exceptionally high generality with respect to amine coupling partners is observed. Specifically, primary and secondary aliphatic and aromatic amines, heterocycles, such as indoles, pyrazole, and carbazole, sulfonamides, as well as electron-deficient aromatic and heteroaromatic amines are competent coupling components.

| S-EPMC4829344 | biostudies-literature