Trialkylsilyl group migration, from

Metal-promoted 1,2-migration of silyl groups in silylalkynes results in the formation of silylvinylidenes which are subsequently readily desilylated. " Alkynyl-substituted silylvinylidenes have been obtained from silylated diynes and the Fe(N2)(CO)2 P(OMe)3 2/ Fe(CO)2[P(OMe)3]2 2(/t-N2) reagent and similar species are implicated in the reactions of several Group 8 metal complexes with mono- and bis-trialkylsilyl diynes. " ... 

On the other hand, an intermolecular migration of silyl groups also takes place among 5-methyl-2-(trialkylsilyl)thiophenetricarbonylchromium(0) complexes under basic conditions45. Increased steric hindrance from the silyl groups (see entry 34 of Table 1) results in preferential deprotonation. 

Migration of trialkylsilyl and germanyl groups from sulphur to aromatic carbon was also observed . Lithiation of 4-bromo-S-trimethylsilyl-benzenethiol (6) yields the lithium salt of 4-trimethylsilylbenzenethiol (7). The mechanism has not been investigated and it has not been established whether an intra- or intermolecular process is involved. 

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