Max-Planck-Institut für Kohlenforschung

Brønsted Acid Catalysis

Evolution of the Brønsted acid catalysts developed in our group and presentation of the general catalytic cycle of asymmetric counteranion-directed Brønsted acid catalysis. Shows molecular structures and a schematic catalytic cycle.

Evolution of the Brønsted acid catalysts developed in our group and presentation of the general catalytic cycle of asymmetric counteranion-directed Brønsted acid catalysis. Shows molecular structures and a schematic catalytic cycle.

The majority of all chemical reactions can be catalysed by Brønsted acids, as the fundamental prerequisite of amenable substrates is the presence of electron density. A core part of our work involves designing and applying highly reactive and selective chiral catalyst motifs for asymmetric counteranion-directed catalysis (ACDC). Integrating tuneable Brønsted acidity within a chiral, confined, enzyme-like microenvironment has led to the development of several classes of catalysts with unique selectivity, as demonstrated in a large number of asymmetric transformations. Our current research aims to expand and generalise the range of available substrates by developing more active, yet highly selective, confined catalyst motifs. Ultimately, we strive to apply our catalysts to real-world examples while addressing long-standing fundamental challenges in chemical synthesis.

Diagram shows (S)-TRIP catalyst used in asymmetric hydrogenation of imines, indicating efficiency.

A Powerful Brønsted Acid Catalyst for the Organocatalytic Asymmetric Transfer Hydrogenation of Imines

Diagram shows kinetic resolution of homoaldol with catalyst and product details, including conversion rates.

Kinetic Resolution of Homoaldols via Catalytic Asymmetric Transacetalization

Illustration of catalytic process for asymmetric spiroacetalization with details on the catalyst and reaction results.

Asymmetric spiroacetalization catalysed by confined Brønsted acids

Diagram showing asymmetric Torgov cyclization for synthesizing estrone with molecular structures and reaction conditions.

Catalytic Asymmetric Torgov Cyclization: A Concise Total Synthesis of (+)-Estrone

Diagram illustrating chemical synthesis with molecular structures, reaction conditions, and perfume ingredients.

A General Catalytic Asymmetric Prins Cyclization

Chemical synthesis diagram showing catalytic asymmetric cycloaddition of dienes with aldehydes, yielding Verdiosa, Doremox, and Pelargene.

Catalytic Asymmetric [4+2]-Cycloaddition of Dienes with Aldehydes

Chemical process diagram showing olefin activation via catalysts, including Boivinainin A and (S)-Mefruside analogue.

Activation of olefins via asymmetric Brønsted acid catalysis

Chemical process diagram illustrating asymmetric Nazarov cyclization steps and yields.

Strong and Confined Acids Enable a Catalytic Asymmetric Nazarov Cyclization of Simple Divinyl Ketones

Diagram illustrating catalytic control with chemical structures and arrows; includes percentages.

Catalytic enantiocontrol over a non-classical carbocation

Diagram showing chemical structures, annotations on acidity and catalyst scaffolds.

Unified Approach to Imidodiphosphate-Type Brønsted Acids with Tunable Confinement and Acidity

Catalytic asymmetric reaction diagram showing synthesis of chamigrene, omphalic acid, and laurenenone C.

Catalytic Asymmetric Spirocyclizing Diels–Alder Reactions of Enones: Stereoselective Total and Formal Syntheses of α-Chamigrene, β-Chamigrene, Laurencenone C, Colletoic Acid, and Omphalic Acid

Chemical process diagram showing asymmetric synthesis of silicon stereogenic centers with various derivatizations.

Organocatalytic Asymmetric Synthesis of Si-Stereogenic Silyl Ethers

Diagram illustrating catalytic synthesis of alkaloids using Pictet-Spengler method and new catalyst design.

A Catalytic Asymmetric Pictet–Spengler Platform as a Biomimetic Diversification Strategy toward Naturally Occurring Alkaloids

Flowchart detailing the synthesis of menthol and cannabinoids from nerol using catalytic methods.

Catalytic asymmetric synthesis of cannabinoids and menthol from neral

Diagram of asymmetric catalytic Friedel-Crafts reactions with chemical structures and reaction conditions.

Asymmetric Catalytic Friedel–Crafts Reactions of Unactivated Arenes

Diagram illustrating secondary benzylic cation reactions with catalytic agents and stereocontrol.

Taming secondary benzylic cations in catalytic asymmetric S_N1 reactions

Chemical reaction diagram with molecular structures and catalysts.

Catalytic asymmetric cationic shifts of aliphatic hydrocarbons

Visual representation of homofarnesol's conversion to Ambrox, highlighting yield and stereochemistry.

The catalytic asymmetric polyene cyclization of homofarnesol to ambrox

Chemical structures and processes illustrating asymmetric cycloadditions using a solid organic framework.

A solid noncovalent organic double-helix framework catalyzes asymmetric [6 + 4] cycloaddition

Illustration showing catalytic process for cyclopropane fragmentation with chemical structures.

Catalytic asymmetric fragmentation of cyclopropanes

Chemical Structures

Catalytic Asymmetric Cycloaddition of Olefins with In Situ Generated N-Boc-Formaldimine

Diagram of Diels-Alder reactions showing chemical structures and synthesis steps.

Catalytic Enantioselective Diels–Alder Reaction of Dienes with Acyclic and α,β- and β,β-Disubstituted Enones