A quantum chemical study has been carried out on the complexes formed in the first stage of the reaction of (chloromethyl)-trifluorosilane with an ambident nucleophile, N-trimethylsilyl-N-methylacetamide, existing in the amide and imidate tautomeric forms. The analysis of molecular electrostatic potential maps of the electrophile molecule revealed the presence of two sigma-holes belonging to the Si and C atoms. Each of the two tautomers of the nucleophile form complexes having O center dot center dot center dot Si, O center dot center dot center dot C, N center dot center dot center dot Si, and N center dot center dot center dot C bonds of different characters. The natural bond orbital and quantum theory of atoms in molecules analyses showed the presence of the O center dot center dot center dot Si and O center dot center dot center dot C tetrel bonds or of electrostatic interaction in the complexes with the amide tautomer, depending on the orientation of the components. The imidate tautomer forms a complex with covalent N-Si bond, whereas the N center dot center dot center dot C bond is very weak. The effect of silicon atom arrangement on the structure of complexes between N-trimethylsilyl-N-methylacetamide and bifunctional silanes ClCH2SiXnF3-n (X = Me, OMe, Cl, n = 1, 2) and the effect of sigma-hole tetrel bonding interactions on the reaction pathways are discussed.