Bicyclobutanes as unusual building blocks for complexity generation in organic synthesis

Bicyclobutanes are among the most highly strained isolable organic compounds and their associated low activation barriers to reactivity make them intriguing building-blocks in organic chemistry. In recent years, numerous creative synthetic strategies exploiting their heightened reactivity have been presented and these discoveries have often gone hand-in-hand with the development of more practical routes for their synthesis. Their proclivity as strain-release reagents through their weak central C-C bond has been harnessed in a variety of addition, rearrangement and insertion reactions, providing rapid access to a rich tapestry of complex molecular scaffolds. This review will provide an overview of the different options available for bicyclobutane synthesis, the main classes of compounds that can be prepared from bicyclobutanes, and the associated modes of reactivity used.

Automated summary

Bicyclobutanes, highly strained isolable organic compounds, have attracted a lot of attention in organic chemistry due to their low reactivity. In recent years, creative synthetic strategies have been developed to exploit their reactivity, leading to the synthesis of more practical routes. The weak central C-C bond in bicyclobutanes has been utilized in various addition, rearrangement and insertion reactions, offering quick access to complex molecular scaffolds. This review provides an overview of different options for bicyclobutane synthesis, the compounds that can be prepared from bicyclobutanes, and the associated modes of reactivity.