Catalytic hydrogenation of 1,8-bis(dimethylamino)-2-nitronaphthalene afford
ed previously unknown 2-amino-1,8-bis(dimethylamino)naphthalene. Its N-acet
yl derivative and 1,2,8-tris(dimethylamino)naphthalene were prepared. The p
K(a)(I) values of the 2-NH2-, 2-NHAc-, and 2-NMe2-substituted "proton spong
es" determined by a competition method in DMSO are equal to 10.3, 7.5, and
9.0, respectively.