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I’m experiencing difficulties putting together a full name of the tertiary amine. One substituent is propyltrimethoxysilane $\ce{(OEt)3Si-CH2-CH2-CH2\bond{-}}$, and the two others are dimethylacetamide $\ce{(CH3)2N-CO-CH2\bond{-}}$ moieties:

Tertiary amine molecule

Thus, could the molecule's name be something like 1,2-dimethylacetamide-3-propyltrimethoxysilane amine?

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The suggested name “1,2-dimethylacetamide-3-propyltrimethoxysilane amine” is not correct for multiple reasons. What are the locants 1, 2, and 3 referring to? There is only one “dimethylacetamide” in the name but there are two in the structure. There is a “trimethoxysilane” in the name but it's a triethoxysilane in the structure. The order of substituents in “3-propyltrimethoxysilane amine” does not correspond to the structure, which is 3-(triethoxysilyl)propan-1-amine. (Also the name “propyltrimethoxysilane” in the question and the label “3-methoxypropylsilane” are wrong.)

Concerning characteristic groups, amides are senior to amines. Thus the smallest parent structure that contains both functional groups would be 2-amino-N,N-dimethylacetamide and not “2-(dimethylamino)-2-oxoethan-1-amine”.

In this case, however, another rule is relevant. Since there are two identical parent structures (the two N,N-dimethylacetamide units), which are not alkanes, multiplicative nomenclature is preferred to substitutive nomenclature.

P-51.3.1 Preferred IUPAC multiplicative names
For a multiplicative name to be categorized as an IUPAC preferred name, certain restrictive conditions must be met. Multiplicative nomenclature is preferred to substitutive nomenclature for generating preferred IUPAC names to express multiple occurrences of identical parent structures, other than alkanes when

(1) the linking bonds (single or multiple) between the central substituent group of the multiplicative group and all subsequent structural units are identical and

(2) the multiplicative groups, other than the central multiplicative group, are symmetrically substituted; and

(3) the locants of all substituent groups on the identical parent structures, including suffix groups, are identical.

Therefore, the identical parent structures are expressed by the multiplicative name 2,2'-…bis(N,N-dimethylacetamide). The preselected prefix azanediyl derived from the preselected parent hydride name “azane” is now used for the multiplicative substituent group $\ce{{}-NH-{}}$. So the complete multiplicative name is 2,2'-azanediylbis(N,N-dimethylacetamide).

The rest of the name is formed using the usual substitutive nomenclature. Thus, the complete name of the structure that is given in the question is 2,2'-{[3-(triethoxysilyl)propyl]azanediyl}bis(N,N-dimethylacetamide)

2,2'-{[3-(triethoxysilyl)propyl]azanediyl}bis(*N*,*N*-dimethylacetamide)
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