Unfortunately, there are three sytems of nomenclature of the amines:
a)The scientific I.U.P.A.C. system consistent with the → table of functional groups :
N,N-dimethylbutan-2-amine
b)The ancient system still in use where the nitrogen atom alone acts as the main chain, all branches on the nitrogen being considered as side chains :
Dimethylpropylamine
c)A third deprecated system, where the nitrogen atom is always designated by the prefix amino.
1-(methylamino)propane