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1.
Sci Adv ; 10(14): eadn1272, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578992

RESUMEN

Direct conversion of hydrocarbons into amines represents an important and atom-economic goal in chemistry for decades. However, intermolecular cross-coupling of terminal alkenes with amines to form branched amines remains extremely challenging. Here, a visible-light and Co-dual catalyzed direct allylic C─H amination of alkenes with free amines to afford branched amines has been developed. Notably, challenging aliphatic amines with strong coordinating effect can be directly used as C─N coupling partner to couple with allylic C─H bond to form advanced amines with molecular complexity. Moreover, the reaction proceeds with exclusive regio- and chemoselectivity at more steric hinder position to deliver primary, secondary, and tertiary aliphatic amines with diverse substitution patterns that are difficult to access otherwise.

2.
World J Clin Cases ; 11(15): 3552-3559, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37383916

RESUMEN

BACKGROUND: Immune-mediated necrotizing myopathy is a rare autoimmune myopathy characterized by muscle weakness and elevated serum creatine kinase, with unique skeletal muscle pathology and magnetic resonance imaging features. CASE SUMMARY: In this paper, two patients are reported: One was positive for anti-signal recognition particle antibody, and the other was positive for anti-3-hydroxy-3-methylglutaryl coenzyme A reductase antibody. CONCLUSION: The clinical characteristics and treatment of the two patients were analysed, and the literature was reviewed to improve the recognition, diagnosis, and treatment of this disease.

3.
Nat Commun ; 14(1): 2938, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217551

RESUMEN

α-Tertiary aliphatic amides are key elements in organic molecules, which are abundantly present in natural products, pharmaceuticals, agrochemicals, and functional organic materials. Enantioconvergent alkyl-alkyl bond-forming process is one of the most straightforward and efficient, yet highly challenging ways to build such stereogenic carbon centers. Herein, we report an enantioselective alkyl-alkyl cross-coupling between two different alkyl electrophiles to access α-tertiary aliphatic amides. With a newly-developed chiral tridentate ligand, two distinct alkyl halides were successfully cross-coupled together to forge an alkyl-alkyl bond enantioselectively under reductive conditions. Mechanistic investigations reveal that one alkyl halides exclusively undergo oxidative addition with nickel versus in-situ formation of alkyl zinc reagents from the other alkyl halides, rendering formal reductive alkyl-alkyl cross-coupling from easily available alkyl electrophiles without preformation of organometallic reagents.

4.
Angew Chem Int Ed Engl ; 61(23): e202200773, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35286774

RESUMEN

Direct alkylation of the C-H bond arenes in a selective manner is a long-standing challenge. Herein, a metal-free photocatalytic regioselective C-H alkylation method for electron-rich arenes with both activated and unactivated alkenes was developed. The reaction tolerates a wide range of aromatic rings with diverse substitution patterns, as well as terminal and internal alkenes, providing a general and straightforward metal-free method for C-C bond formation from inert C-H bonds. Moreover, alkynes are also compatible to give the C-H vinylation of electron-rich arenes.

5.
Nat Commun ; 12(1): 2771, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33986269

RESUMEN

Chiral aliphatic amine and alcohol derivatives are ubiquitous in pharmaceuticals, pesticides, natural products and fine chemicals, yet difficult to access due to the challenge to differentiate between the spatially and electronically similar alkyl groups. Herein, we report a nickel-catalyzed enantioselective hydroalkylation of acyl enamines and enol esters with alkyl halides to afford enantioenriched α-branched aliphatic acyl amines and esters in good yields with excellent levels of enantioselectivity. The operationally simple protocol provides a straightforward access to chiral secondary alkyl-substituted amine and secondary alkyl-substituted alcohol derivatives from simple starting materials with great functional group tolerance.

6.
Angew Chem Int Ed Engl ; 60(18): 9875-9880, 2021 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-33539628

RESUMEN

Direct and selective synthesis of primary amines from easily available precursors is attractive yet challenging. Herein, we report the rapid synthesis of primary amines from alkenes via metal-free regioselective hydroamination at room temperature. Ammonium carbonate was used as ammonia surrogate for the first time, allowing for efficient conversion of terminal and internal alkenes into linear, α-branched, and α-tertiary primary amines under mild conditions. This method provides a straightforward and powerful approach to a wide spectrum of advanced, highly functionalized primary amines which are of particular interest in pharmaceutical chemistry and other areas.

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