Chromeno[4,3-b]chromene is a ubiquitous structural motif found in various pharmaceuticals and biologically active compounds. A concise palladium-catalyzed reaction of vinyl iodides and salicyl N-tosylhydrazones has been achieved to afford a series of compounds containing the chromeno[4,3-b]chromene scaffold in moderate to high yield. This tandem reaction involves palladium(II) carbene migratory insertion and intramolecular cyclization assisted by an O nucleophile and tolerates various functional groups.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.joc.5b00500 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Three-component diels-alder reaction through palladium carbene migratory insertion enabled dearomative C(sp)-H bond activation.
Nat Commun
December 2024
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan, 410081, China.
Owning to the versatile nature in participation of Diels-Alder (D-A) reactions, the development of efficient approaches to generate active ortho-quinodimethanes (o-QDMs) has gained much attention. However, a catalytic method involving coupling of two readily accessible components to construct o-QDMs is lacking. Herein, we describe a palladium carbene migratory insertion enabled dearomative C(sp)-H activation to form active o-QDM species through the cross-coupling of N-tosylhydrazones with aryl halides.
View Article and Find Full Text PDFRare-earth metal complexes bearing electrophilic and nucleophilic carbon centres and their unique reactivity patterns towards pyridine derivatives.
Chem Sci
December 2024
Anhui Laboratory of Clean Catalytic Engineering, Anhui Laboratory of Functional Coordinated Complexes for Materials Chemistry and Application, College of Chemical and Environmental Engineering, Anhui Polytechnic University Wuhu 241000 Anhui P. R. China
The rare-earth metal dialkyl complexes (κ-L)RE(CHSiMe)·(THF) [RE = Lu(1a), Yb(1b), Er(1c), Y(1d), Dy(1e)] (L = 1-(2--CHNCHCH)-3-(2,6-PrCHN[double bond, length as m-dash]CH)-CHN) and the rare-earth metal monoalkyl complexes (κ-L)RE(CHSiMe)·(THF) [ = 0, RE = Lu(2a), Yb(2b); = 1, Er(2c), Y(2d), Dy(2e)], (κ-L)RE(CHSiMe)·THF [RE = Yb(3a), Er(3b), Y(3c), Dy(3d), Gd(3e)] (L = 1-(2--CHNCHCH)-3-(AdN[double bond, length as m-dash]CH)-CHN) (Ad = adamantyl, CH) have been synthesized and fully characterized. These complexes feature chelate ligands having a conjugated system (-C[double bond, length as m-dash]C-C[double bond, length as m-dash]N) with an sp carbon, which enables both electrophilic and nucleophilic carbon centres to be directly connected to the highly electrophilic rare-earth metal ions. The reactions of these complexes with different pyridine derivatives have been systematically investigated with the discovery of reactivity patterns distinct from those of previously reported transition metal complexes.
View Article and Find Full Text PDFSolvent-Controlled Rh(III)-Catalyzed Mono- and Dual Functionalization of Quinolyl Aldoximes with Diazo Compounds.
J Org Chem
December 2024
Guangdong Provincial Key Laboratory of Chiral Molecules and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
A solvent-controlled Rh(III)-catalyzed mono- and dual-C-H bond activation/carbene migratory insertion with diazo compounds as a single coupling partner was demonstrated. The reaction proceeded under mild conditions, yielding products in good to excellent yields. These results are significant for the development of the domino multiple functionalization of C(sp)-H bonds via a carbenoid insertion approach.
View Article and Find Full Text PDFRu-Catalyzed C-H Alkylation of 4-Aryl-pyrrolo[2,3-]pyrimidines with Diazo Compounds: An Access to Fluorescent Fused Heteroarenes.
J Org Chem
December 2024
College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
A Ru(II)-catalyzed migratory insertion of carbene into C-H bonds of 4-aryl-pyrrolo[2,3-]pyrimidines has been developed. This transformation endows the facile fabrication of C-C bonds with high atom economy, good regioselectivity, and wide functional group tolerance, exploiting the directing properties of pyrimidinic nitrogen. In addition, the planar polycyclic pyrrolo-pyrimido-isoindole framework has been accomplished from a cascade reaction of bromination, cyclization, and decarboxylation of synthesized products.
View Article and Find Full Text PDFRemote Catalytic C(sp)-H Alkylation via Relayed Carbenoid Transfer upon Olefin Chain Walking.
J Am Chem Soc
November 2024
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea.
Transition metal carbenes have emerged as versatile intermediates for various types of alkylations. While reactions of metal carbene species with alkenes have been extensively studied, most examples focus on cyclopropanation and allylic C-H insertion. Herein, we present the first example of a catalytic strategy for the carbene-involved regioselective remote C-H alkylation of internal olefins by synergistically combining two iridium-mediated reactivities of olefin chain walking and carbenoid migratory insertion.
View Article and Find Full Text PDFWant 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!