Modular Access to Diverse Chemiluminescent Dioxetane-Luminophores through Convergent Synthesis.

Adamantyl-dioxetane luminophores are an important class of chemiluminescent molecular probes for diagnostics and imaging. We have developed a new efficient synthetic route for preparation of adamantyl-enolether as precursors for dioxetane chemiluminescent luminophores. The synthesis is convergent, using an unusual Stille cross-coupling reaction employing a stannane-enolether, to directly afford adamantyl-enolether. In a following simple step, the dioxetane is obtained by oxidation of the enolether precursor with singlet-oxygen. The scope of this synthetic route is broad since a large number of haloaryl substrates are either commercially available or easily accessible. Such a late-stage derivatization strategy simplifies the rapid exploration of novel luminogenic molecular structures in a library format and simplifies the synthesis of known dioxetane luminophores. We expect that this new synthetic strategy will be particularly useful in the design and synthesis of yet unexplored dioxetane chemiluminescent luminophores.