The proton sponge 1,8-bis(dimethylamino)naphthalene: The quicker-picker-upper also for s-block metal cations?

1,8-bis-(dimethylamino)-naphthalene, the first ever reported proton sponge, has been snatching much attention with its spectacular proton affinity (PA) for decades. This manuscript discusses the affinities of DMAN towards s-block metal ions Li+, Na+, K+, Be++, Mg++ and Ca++ and compare with PA. We report that the affinity of DMAN towards Be++ is higher than PA. It was observed that increasing methylation at the peri-nitrogen atoms increases the beryllium ion affinity like PA. In light of all these discussions, this manuscript discusses if DMAN can better be termed as a beryllium ion sponge.