29Si NMR Investigation of Si‐alkylsubstituted 1,3,5‐Trisilacyclohexanes

²⁹Si NMR spectra of 29 Si‐alkylsubstituted derivatives of 1,3,5‐trisilacyclohexanes have been recorded and analyzed. A systematic preparation of alkyl derivatives with mixed substituents made it possible to evaluate substituent‐induced chemical shift (SCS) values for the ring silicon atoms in α and γ position. It is found that the equatorial α‐effect increases in the order Me < Et < i‐Pr < t‐Bu. For the alkyl groups Me, Et, and i‐Pr the axial α‐effect is similar in magnitude to the α_e‐effect. Axial SCS values for the t‐Bu group are not accessible because chair conformations with an axial t‐Bu group are energetically unfavourable and escape into a twisted boat form. The observed γ‐effects exhibit the γ_gauche‐effect for axial substituents as known from compounds with a pure carbon framework.