Following our computational analysis, we carried out several attempts to reduce 1-AE and 3-AE, however we have not been able to produce our target reduced species. In the case of 1-Ca, we performed attempted reductions with KC8 either with 18-crown-6 in THF, or in benzene without any sequestering agent (for the latter we used [Ca{N(SiMe3)2}3K] as starting material, rather than 1-Ca). In both cases we recovered unreacted starting material and K[N(SiMe3)2],