Selective Synthesis of Boron-Functionalized Indenes and Benzofulvenes by BCl3-Promoted Cyclizations of ortho-Alkynylstyrenes.

ABSTRACT

A selective, metal-free synthesis of boron-functionalized indenes and benzofulvenes via BCl3-mediated cyclization of o-alkynylstyrenes is described. The method allows precise control over product formation by adjusting reaction conditions. These borylated products were utilized in diverse C-B bond derivatizations and in the total synthesis of Sulindac, a nonsteroidal anti-inflammatory drug, demonstrating the versatility and practicality of the developed methodology for synthetic applications.