After forming (3-methoxythiophen-2-yl)trimethylsilane, I react it with 1 eq of nBuLi and quench with snbu3cl - obtaining starting material. Is the nBuLi acting the tms group?
Dear Yasmin Choaie , just in case that this is still of interest to you: Attached please find an article in which some points of your question are addressed.