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Construction of all-carbon quaternary centres is an important task in organic synthesis. In spite of the challenges associated with the Csp3-Csp3 bond constructions in a sterically constrained environment, significant advances have been made in this area. Among the latter, catalytic and non-catalytic [3+2] cycloaddition approach has gained wide attention recently. This short review summarizes the [3+2] cycloaddition reactions reported during the period 2016-2022 for the synthesis of molecules possessing one or more all-carbon quaternary stereocentre

The utility of donor-acceptor cyclopropanes (DACs) for the construction of heterocycles is discussed here. In addition to (3+2), (3+3) and (4+3) cycloaddition pathways, nucleophilic ring-opening reactions, intramolecular transformations and cycloisomerizations in presence of suitable catalysts pave way for the generation of heterocycles from DACs. Mild reactions conditions employed and the variety of starting materials that can be used as reaction partners makes the DAC route for heterocycle synthesis attractive. The literature from 2018-2023 is categorized as below. 1 Introduction 2 Synthesis of Nitrogen heterocycles 2.1 By annulations with anthranils and azadienes 2.2 By nucleophilic attack of anilines and hydrazones 2.3 By reaction with ureas and thioureas 2.4 By annulation reactions using azomethine imine 2.5 By reaction with other N-heterocycles 2.6 By other transformations 3 Synthesis of Oxygen heterocycles 3.1 By intramolecular transformations 3.2 By intermolecular reactions 4 Synthesis of Sulphur/Selenium heterocycles 4.1 By reaction with thiocarbonyl substrates 4.2 By reaction with thio/selenocyanates and thiosulfonate salts 5 Synthesis of N-S/O heterocycles 6 Conclusions