A class of chemical compounds known as isochromenes is made up of a bicyclic structure made up of a fused benzene ring and a cyclopentene ring. Their variable reactivity and prospective uses in a range of domains, including organic synthesis, materials science, and medicines, make them of great interest in organic chemistry. They also exhibit a diversity of chemical characteristics. The aromaticity of isochromenes is a fundamental feature that results from the resonance stabilization that the π-electron system of the benzene ring provides. This aromaticity affects the molecule's chemical behavior and gives it stability. A wide range of functionalized derivatives can be formed by isochromenes undergoing a number of reactions, such as ring-opening reactions, nucleophilic addition, and electrophilic aromatic substitution. Different synthetic techniques are used to create isochromenes, based on the functional groups and desired substitution pattern. To obtain the isochromene scaffold, a typical method is to intramolecularly cyclize enynes or dienynes and then aromatize the resultant product. Photochemical transformations and cyclization processes catalyzed by transition metals are alternative tactics. Isochromenes have been used in medicinal chemistry, where they are preferred building blocks for creating bioactive substances. The isochromene motif is a key component of many natural compounds and pharmacological medicines, demonstrating its importance in medication development and discovery. Furthermore, a variety of biological actions, such as anticancer, antibacterial, anti-inflammatory, and antioxidant qualities, are exhibited by isochromene derivatives, which makes them a promising option for lead optimization and drug candidates. Isochromenes have been investigated in materials science as possible building blocks for the creation of useful materials. Their distinct structural characteristics, in conjunction with their synthetic accessibility and adjustable reactivity, render them appealing subjects for the development of customized molecular scaffolds. Applications for isochromene-based polymers and materials in organic electronics, optoelectronics, and sensors have been studied. All things considered, isochromenes' varied chemistry and wide range of uses emphasize their significance as useful molecular scaffolds and synthetic intermediates in organic chemistry. The breadth of their use in numerous domains is anticipated to grow further with ongoing research endeavors focused on creating novel synthetic techniques and investigating their functional characteristics.
