An unusual chemoselective 1,1-addition
of α-C2-bridged biphospholes to terminal alkynes
is reported. The developed
protocol provides simple access to the unknown 1,3-diphosphepines,
which has potential applications in the coordination and catalyst
chemistry. Their Pd and Mo complexes were studied by single-crystal
X-ray diffraction analysis. This method features excellent chemoselectivity,
high step and atom economy, mild reaction conditions, and wide substrate
scope.