Related Experiment Video

Updated: Mar 29, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Published on: February 7, 2019

Practical Organocatalytic Synthesis of Functionalized Non-C2-Symmetrical Atropisomeric Biaryls

Hongyin Gao¹, Qing-Long Xu¹, Craig Keene¹

¹Department of Chemistry, Rice University, BioScience Research Collaborative, 6500 Main Street, Rm 380, Houston, TX, 77030 (USA).

Angewandte Chemie (International Ed. in English)

|November 24, 2015

Abstract:

An organic acid catalyzed direct arylation of aromatic C(sp(2))-H bonds in phenols and naphthols for the preparation of 1,1'-linked functionalized biaryls was developed. The products are non-C2-symmetrical, atropoisomeric, and represent previously untapped chemical space. Overall this transformation is operationally simple, does not require an external oxidant, is readily scaled up (up to 98 mmol), and the structurally diverse 2,2'-dihydroxy biaryl (i.e., BINOL-type), as well as 2-amino-2'-hydroxy products (i.e., NOBIN-type) are formed with complete regioselectivity. Density-functional calculations suggest that the quinone and imino-quinone monoacetal coupling partners are exclusively arylated at their α-position by an asynchronous [3,3]-sigmatropic rearrangement of a mixed acetal species which is formed in situ under the reaction conditions.

Keywords:

atropisomerism biaryls organocatalysis rearrangements synthetic methods

More Related Videos

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Published on: May 26, 2019

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Related Concept Videos

Regioselectivity and Stereochemistry of Hydroboration

Regioselectivity and Stereochemistry of Hydroboration

A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction

α-Substituted ketones or aldehydes can be synthesized from enamines by the Stork enamine reaction, named after its pioneer Gilbert Stork. Enamines are useful synthetic intermediates where the lone pair on nitrogen is in conjugation with the C=C bond. They resemble enolate ions, as the resonance forms of both species have a nucleophilic α carbon.

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.

Articles linked to this work by shared authors, journal, and citation graph.

N-Phenylhydroxylamine-Induced Radical Relay for the Synthesis of α-Trifluoromethyl Ketones.

Organic letters·2026

O-Vinylhydroxylamines for De Novo Pyrrole Synthesis.

Journal of the American Chemical Society·2026

Hydrodefluorination of a Fluorobenzene Equivalent by Harnessing a P(III)/Pd(II)-P(V)/Pd(0) Redox Couple Using a P-CF3-Functionalized Benzazaphosphole.

Inorganic chemistry·2026

Non-radical pathways control methane sulfonation versus oxygenation C-H functionalization selectivity with Hg(ii) and Au(iii) catalysis.

Chemical science·2026

para-Selective C-H Arylation and Alkylation of N-Arylhydroxylamines.

Organic letters·2026

Synthesis and Characterization of a Copper Complex Supported by a Z‑type SbV Ligand: XPS and DFT Study of Electronic Structure.

Organometallics·2026

See all related articles