Computational insight into the reductive oligomerisation of CO at uranium(III) mixed-sandwich complexes

Calculations reveal a multistep pathway towards formation of linear [U](2)-(mu-eta(1):eta(1)-C2O2); [U] = U(eta-C8H6{SiH3-1,4}(2))(eta-Cp). However formation of deltate-bridged [U](2)-(mu-eta(1):eta(2)-C3O3) requires an alternative mechanism, involving a side-on [U](2)-(mu-eta(2):eta(2)-CO) complex and whereby the bridging units of [U](2)-(mu-eta(2):eta(2)-CnOn) intermediates (n = 1, 2) react directly with free CO.