1,3-Dehydroadamantane and Its Derivatives: A Versatile Synthetic Platform for the Preparation of Functional Compounds with a Cage Structure. A Review

Abstract

A promising strategy in the synthesis of functional compounds with a cage structure is the use of 1,3-dehydroadamantane (tetracyclo[3.3.1.1.^3,7.0.^1,3]decane; 1,3-DHA; bridging [3.3.1]propellane) and its derivatives that are capable of restoring the adamantane structure in their reactions. The review provides information on the methods for the synthesis of 1,3-DHA, spectral characteristics, probable intermediates generated from propellanes, and the advantages of their using: low-stage syntheses of difficult-to synthesize adamantane derivatives, atomic precision, and “green chemistry.” The reactions of 1,3-DHA with a wide range of organic compounds are considered, and its reactivity with respect to CH-, NH-, OH-, and SH-acids, as well as arenes, hydantoins, and heterocyclic compounds, is compared. New chemo- and regioselective methods for the one-step introduction of a 1-adamantyl group into the molecules of various substrates are classified. Particular attention is paid to the reactions of 1,3-DHA with various C–H acids, which enable the easy formation of C–C_Ad bonds to give hard-to-synthesize adamantane derivatives. The influence of pK_a of the substrate on the selectivity of the reactions is demonstrated. Low-step methods for the synthesis of new adamantane derivatives, which have shown high activity as hsEH epoxide hydrolase inhibitors and antitumor agents, are described.