Versatile Dibenzothio[seleno]phenes via Hexadehydro-Diels-Alder Domino Cyclization.

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Dibenzoselenophenes and dibenzothiophenes are important heterocyclic compounds found in natural products.
• Existing synthesis methods can be complex and lack efficiency for creating highly substituted analogs.

Purpose of the Study:

• To develop a facile and efficient strategy for synthesizing highly substituted dibenzoselenophenes and dibenzothiophenes.
• To explore a novel domino hexadehydro-Diels-Alder reaction for constructing fused heterocycles.

Main Methods:

• A domino hexadehydro-Diels-Alder reaction was employed.
• The reaction involved one-pot, multi-terminal cycloaddition reactions.
• Tetraynes were reacted with triphenylphosphine selenide or sulfide.

Main Results:

• The synthesis of highly substituted tetracyclic dibenzoselenophenes and dibenzothiophenes was achieved.
• The reaction successfully formed three new C-C bonds and one new Caryl-Se/Caryl-S bond.
• A C-H σ-bond migration was observed as part of the multi-step transformation.

Conclusions:

• The reported domino reaction is a robust and efficient method for synthesizing complex fused heterocycles.
• This strategy is pivotal for constructing highly substituted natural thio[seleno]phene cores.
• The method offers a valuable tool for organic chemists seeking to produce diverse heterocyclic structures.