Several trimethylsilyl substituted 1-phenyl or 1-benzyl isoquinoline derivatives were synthesized by the Bishler–Napieralsky reaction starting from the corresponding homoveratrylamides, which were cyclized in toluene in the presence of phosphorus pentoxide or phosphorus oxychloride. These conditions were suitable for the homoveratrylamides ofp- oro-trimethylsilylbenzoic acid andp-trimethylsilylmethylphenylacetic acid but not for that ofp-trimethylsilylphenylacetic acid, due to the greater sensitivity of the silicon–aryl bond in the latter to cleavage under acid conditions.Some 2-aralkyl imidazolines containing a trialkylsilyl group in the para-position were synthesized by condensation of silicon-containing aromatic acids and ethylenediamine.SeveralN-substitutedp-trialkylsilyl phenethylamines were prepared by lithium aluminium hydride reduction of the corresponding amides.