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Owing to the importance of arene moieties in organic chemistry, methods for arene construction attract great attention. Besides the traditional substitution strategy from pre-existing arenes, the straightforward formation of arene cores can also provide significant shortcuts towards a wide array of target molecules with different substitution patterns. Among direct arene formation reactions, applying environmentally benign organocatalysis to access arene moieties continues to attract increasing attention. This short review provides a brief summary of recent progress on organocatalyzed de novo (hetero)arene formation and applications in enantioselective synthesis. 1 Introduction 2 Arene Formation with Non-Covalent Organocatalysts 2.1 Arene Formation with Acid Organocatalysts 2.2 Arene Formation with Base Organocatalysts 2.3 Arene Formation with Hydrogen-Bonding Organocatalysts 3 Arene Formation with Covalent Organocatalysts 3.1 Arene Formation with Lewis Base Organocatalysts 3.1.1 Arene Formation with Secondary Amine Organocatalysts 3.1.2 Arene Formation with Tertiary Amine, Tertiary Phosphine and Sulfide Organocatalysts 3.1.3 Arene Formation with N-Heterocyclic Carbene Organocatalysts 3.2 Arene Formation with Lewis Acid Organocatalysts 4 Conclusion [ABSTRACT FROM AUTHOR]

Multisubstituted arenes such as indanes with attached all‐carbon quaternary centers are unique scaffolds in synthetic functional molecules and sophisticated natural products. A key challenge in preparing such molecules lies in the enantioselective installation of the quaternary carbon centers. Conventional methods in this direction include asymmetric substitution reactions and substrate‐controlled cyclization reactions. These reactions lead to poor stereoselectivities and/or require long and tedious synthetic steps. Disclosed here is a one‐step organic catalytic strategy for enantioselective access to this class of molecules. The reaction involves an N‐heterocyclic carbene catalyzed process for direct benzene construction, indane formation, remote‐carbon desymmetrization, and excellent chirality control. This approach will enable the concise synthesis of arene‐containing molecules, including those with complex structures and challenging chiral centers. [ABSTRACT FROM AUTHOR]

A new catalytic approach for rapid asymmetric access to spirocycles is disclosed. The reaction involves a carbene‐ and thiourea‐cocatalyzed desymmetrization process with the simultaneous installation of a spirocyclic core. The use of a thiourea cocatalyst is critical to turn on this reaction, as no product was formed in the absence of a thiourea. Our study constitutes the first success in the carbene‐catalyzed enantioselective synthesis of all‐carbon spirocycles. The reaction products can be readily transformed into sophisticated multicyclic molecules and chiral ligands. Harmony between cats: Dual carbene and thiourea catalysis enabled rapid asymmetric access to spirocyclic compounds by a desymmetrization process (see scheme). The presence of the thiourea cocatalyst was essential for this carbene‐catalyzed enantioselective synthesis of all‐carbon spirocycles to proceed. The reaction products can be readily transformed into sophisticated multicyclic molecules and chiral ligands. [ABSTRACT FROM AUTHOR]