Reactivity of Chromium-Selenium Triple Bonds: The First Example of a Planar Cr₃Se Multiple-Bond System Generated via Selective Reduction¹

The recent spate of discoveries of generally applicable synthetic routes to complexes containing multiple bonds between transition metals and unsubstituted (“bare”) main group elements has led, especially in the case of the more electropositive elements of groups 4-6, to a rapid accrual of new compounds of wide structural diversity.³ Initial reactivity studies have revealed close relationships to the chemistry of metal-metal bonds.^3,4 All of the valence electrons of the main group elements often participate in bonding to transition metals resulting in an exceptionally unsaturated bonding situation, with the Cr2Se complex 1 representing a prototypal example.