An unexpected influence of the nature of stabilizing additives to alkyllithium compounds on an aggregate's reactivity was examined experimentally and theoretically.

The combination of an alkoxy and an amino function combined in one silane is rarely found due to the difficult synthesis and isolation.[1] However, this combination offers unique opportunities to investigate the influence of steric requirements or the size of a metal on the structure or reactivity of alkoxysilylamides towards electrophiles by varying the metallating reagent (n‐butyllithium or di‐n‐butylmagnesium) or the organo group on the amino function. For this purpose, we synthesized two alkoxyaminosilanes with acidic NH units that can be metalated. On the one hand, the tert‐butylamino‐substituted (tert‐butylamino)‐methoxydiphenylsilane (1) and on the other hand the isopropylamino‐substituted methoxydiphenyl(isopropylamino)silane (2). The resulting structures showed an interesting interrelation between the Si–O or Si–N bond lengths and the strength of the coordinative bond to the corresponding metal cation (lithium or magnesium).

Trimethyl({tris[(phenylsulfanyl)methyl]silyl}methoxy)silane (3), C26H32OS3Si, is a new ligand for transition-metal coordination chemistry derived from 3-bromo-2,2-bis(bromomethyl)propan-1-ol (1), C5H9Br3O, through silylation and following exchange of bromine groups with NaSPh. Silylated thioether ligand 3 crystallizes in the centrosymmetric space group C2/c. Bromomethylalcohol 1 crystallizes in the space group P\overline{1} in the triclinic crystal system with four molecules in the asymmetric unit. Analysis of the Hirshfeld surface shows structure-defining interactions for bromomethylalcohol 1, resulting in intermolecular hydrogen bonds between the hydroxyl groups along the a-axis direction.