Abstract
The synthesis of allylic sila (and germa) cyclopentenes containing an Et 3M (M Si, Ge) group in vinylic position is described. 1-Germacyclopent-3-enes 3-silylated (IIIa) and 3-germylated (IIIb) result from 1,4-cycloaddition of GeI 2 to the corresponding 2-metallated 1,3-dienes (II). 3-Metallated 1-silacyclopent-3-enes (IIIc–IIIf) are obtained by two methods. One involves the reaction of dienes II with Me 2SiCl 2 and Mg, leading to compounds IIIc (M Si) and IIId (M Ge). The other method corresponds to the trichlorosilylation (HSiCl 3, Et 3N, ϵ Cu 2Cl 2) of dichlorinated compounds I resulting from cis-addition of Et 3MH to cis-1,4-dichlorobutyne. From the two trichlorosilylated derivatives IV and V, formed in S N2 and S N2′ reactions, only the 1-trichlorosilyl 2-triethylsilyl (and germyl) 4-chlorobut-2-enes (IV) give, in the presence of magnesium, the 1,1-dichloro 3-triethylsilyl (and germyl) 1-silacyclopent-3-enes (IIIe and IIIf).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
