A one-pot regioselective synthesis of tricyclic 1,1-diphosphines invol
ving, first, insertion reaction of 2,3-dihydrophosphole (3) into the z
irconium-carbon bond of a generated in situ zirconocene benzyne and, t
hen, an exchange reaction between the resulting tricyclic metalated ph
osphine 4 and various dichlorophosphines is reported. One of these I,l
-diphosphines, 15a (bis-(sulfide) adduct), is characterized by single-
crystal X-ray diffraction studies.