The aggregation of a series of mono- and dilithionaphthalenes in THF solutions in the presence of tetramethylethylenediamine (TMEDA) and pentamethyldiethylenetriamine (PMDTA) was studied by NMR spectroscopy and quantum chemical calculations. The stability of dimeric species in diluted solutions as well as reasons of their disaggregation in some cases has been discussed. For the lithioderivatives of 1,8-bis­(dimethylamino)­naphthalene (DMAN) the possibility of NMe2 group coordination to the lithium atom in ortho-position of naphthalene core under steric pressure of substituents was demonstrated by quantum chemical calculations. For the first time, dilithionaphthalenes were studied by 1H, 13C, and 7Li NMR spectroscopy. It was shown that while β-dilithionaphthalenes form oligomeric aggregates in solutions, α-dilithionaphthalenes exist as solely monomeric species with each lithium atom coordinated to both peri-positions.

The bromine-lithium exchange sequence upon interaction of 2,4,5,7-tetrabromo-1,8-bis(dimethylamino)naphthalene with n-BuLi was studied. Experimental results were explained by means of quantum chemical calculations. It was demonstrated that the first exchange occurs in position 4 due to the significant decrease of a steric strain of the molecule. The second exchange takes place in either position 5 or 7 due to the even more negative charge distribution in the naphthalene core. As a result, the third exchange leads to the species containing lithium in positions 2,4,5 or 2,4,7. Using a large excess of n-BuLi in hexane, 2,4,5,7-tetralithio-1,8-bis(dimethylamino)naphthalene was successfully prepared. The latter was used for the synthesis of several tetrasubstituted derivatives of 1,8-bis(dimethylamino)naphthalene by quenching with different electrophiles.

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