This work is dedicated to Carsten Bolm, in appreciation for hosting the authors’ group
at his chair.
Abstract
Carbocations, often deemed transient and unstable intermediates in organic chemistry,
gained significant recognition with the awarding of the Nobel Prize in Chemistry to
George A. Olah in 1995 for his work on carbocation chemistry. The triphenylmethyl
(trityl) cation, a stable and versatile carbocation, has emerged as a significant
player in organic reactions. This short review provides an update on the use of trityl
cations as organic Lewis acids, highlighting their role in various catalytic processes.
We aim to offer a comprehensive overview of the latest developments and prospects
of these ions. The continued exploration of trityl cations promises to enhance their
role as a valuable tool in synthetic chemistry, offering efficient alternatives to
traditional inorganic or metal-based catalysts.
1 Introduction
2 Synthesis of Fluorinated Triphenylmethylium Acids
3 Redox Behavior of Tritylium Salts
4 Lewis Acids for Organocatalysis
5 Catalysis of Multicomponent Syntheses
6 Initiation of Carbenium- and Silylium-Centered Reactivity
7 Polymer Synthesis
8 Further Applications of Tritylium Salts
9 Conclusion and Outlook
Key words
trityl cation - carbocation - Lewis acid - catalyst - acids - electrophiles - organocatalysis
