Regio- and Chemoselective Formal (4+1) Carbocyclization of Chalcones with Internal Alkynes via Rhodium(III) Catalysis.

Angew Chem Int Ed Engl

Key Laboratory of Chemical Biology and Traditional Chinese Medicine, Ministry of Education of China, Changsha, 410081, China.

Published: July 2023

A rhodium(III)-catalyzed oxidative cyclization of chalcones with internal alkynes is reported, generating biologically important 3,3-disubstituted 1-indanones along with reusable aromatic aldehydes. This transformation features unique (4+1) reaction mode, excellent regioselectivity in alkyne insertion, broad substrate scope, allows for the construction of quaternary carbon centers, and is scalable. Steric hindrance from substrate and ligand probably controls the chemoselectivity of this carbocyclization. Importantly, this discovery enables a practical two-step protocol switching the overall reaction of acetophenones with internal alkynes from a (3+2) to a (4+1) annulation.

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.202305983DOI Listing

Publication Analysis

Top Keywords

internal alkynes
12
chalcones internal
8
regio- chemoselective
4
chemoselective formal
4
formal 4+1
4
4+1 carbocyclization
4
carbocyclization chalcones
4
alkynes rhodiumiii
4
rhodiumiii catalysis
4
catalysis rhodiumiii-catalyzed
4

Similar Publications

Objective: In search of efficient anticancer agents, we aimed at the design and synthesis of a library of tetrasubstituted alkenes. These are structural analogues of tamoxifen, one of the widely used anticancer therapeutics.

Methods: Our small organic compound library was prepared via a chemical synthesis in the solution using the Larock three-component coupling reaction, which is known to tolerate diverse functional groups.

View Article and Find Full Text PDF

Zero-Valent Copper Catalysis Enables Regio- and Stereoselective Difunctionalization of Alkynes.

Angew Chem Int Ed Engl

January 2025

Jain University - Ramanagara Campus, Centre for Nano and Material Sciences, Jakkasandra Post Kanakapura Taluk, Ramanagara-562112, Bangalore, 562112, Bangalore, INDIA.

The development of a metallic copper-based catalyst system remains a significant challenge. Herein, we report the synthesis of highly stable, active, and reusable Cu0 catalyst for the carboboration of alkynes using carbon electrophiles and bis(pinacolato)diboron (B2pin2) as chemical feedstocks to afford di- and trisubstituted vinylboronate esters in a regio- and stereoselective manner with appreciable turnover number (TON) of up to 2535 under mild reaction conditions. This three-component coupling reaction works well with a variety of substituted electrophiles and alkynes with broad functional group tolerance.

View Article and Find Full Text PDF

Tailoring Metal-Organic Frameworks for One-Step Separation of Alkane/Alkene/Alkyne Mixtures.

Chem Asian J

January 2025

Shenzhen Polytechnic University, Hoffmann Institute of Advanced Materials, 7098 Liuxian Blvd., 518055, Shenzhen, CHINA.

The purification of polymer-grade (>99.9%) olefins (mostly C2 and C3) represents a significant yet challenging process in petrochemical industry. The commonly employed method for hydrocarbon separation involves heat-driven distillations.

View Article and Find Full Text PDF

Chiral allyl amines are important structural components in natural products, pharmaceuticals, and chiral catalysts. Herein, we report a cobalt-catalyzed enantioselective reductive coupling of imines with internal alkynes to synthesize chiral allyl amines. The reaction is catalyzed by a cobalt complex derived from commercially available bisphosphine ligand utilizing zinc as the electron donor.

View Article and Find Full Text PDF

Reversible Bimetallic Inhibition to Modulate Selectivity During Catalysis.

J Am Chem Soc

January 2025

Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC). Avenida Américo Vespucio 49, 41092 Sevilla, Spain.

Bimetallic complexes have demonstrated a great ability to enhance the activity of monometallic systems for bond activation and catalysis. In this work, we explore the opposite approach: using a second metal to passivate the activity of another by reversible bimetallic inhibition. To do so we have synthesized a family of nine electrophilic gold complexes of formula Au(PR)(NTf) ([NTf] = [N(SOCF)]) that can act as inhibitors in the semihydrogenation of terminal and internal alkynes catalyzed by the iconic iridium Vaska complex IrCl(CO)(PPh).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!