The ditriflato-diborane B2(μ-hpp)2(OTf)2 (hpp = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate) acts as a stable surrogate of the elusive dication [B2(hpp)2]2+, being both electrophilic (vacant boron p orbitals) and nucleophilic (filled B-B bond orbital). This combination of seemingly contrasting behaviors could be used to develop a metallomimetic diborane chemistry, with Lewis σ-basic and π-acidic substrates being bound and reduced at the diborane. Here, we report on a novel reaction …