NMR and DFT Characterization of Pd Complexes Observed during Pd-Catalyzed Arylation of Hydrodisilanes

The Pd(P( t -Bu) 3 ) 2 -catalyzed arylation of hydrosilanes containing a Si–Si σ bond proceeds under conditions where Si–Si bond cleavage is suppressed, even though transition metals are known to cleave Si–Si bonds; several Pd species were observed during the course of the reaction. The species were identified as (( t -Bu) 3 P)Pd(μ-I)(μ-η 2 -HSiMeR)Pd(P( t -Bu) 3 ) (R = Me ( 7 ) or Ph ( 8 )) based on comprehensive NMR studies and DFT calculations. These complexes are considered to arise from side processes occurring during the catalytic cycle. The structural characterization of these Pd species provides insight into the behavior of hydrodisilanes under Pd catalysis.