Syntheses and Reactivities of Stable Halosilylenoids, (Tsi)X2SiLi (Tsi=C(SiMe3)3, X=Br, Cl)

Halosilylenoids, stable at room temperature (Tsi)X2SiLi (Tsi=C(SiMe3)3, X=Br, Cl), were synthesized from the reaction of TsiSiX3 with lithium naphthalenide. Bromosilylenoid reacted with tBuOH and MeI both at −78 °C and at room temperature to give (Tsi)HSiBr2 and (Tsi)MeSiBr2, respectively, in high yields; this clearly shows its nucleophilicity. In the reaction of bromosilylenoid with methanol, 2‐propanol, and 2,3‐dimethyl‐1,3‐butadiene, the corresponding products, (Tsi)HSi(OMe)2, (Tsi)HSi(OiPr)Br, and bromo(Tsi)silacyclopent‐3‐ene, were obtained in high yields; this demonstrates its amphiphilic property, as if bromosilylene would be trapped. Chlorosilylenoid also exhibited both nucleophilic and amphiphilic properties. The 29Si chemical shifts for (Tsi)Br2SiLi, (Tsi)Br2SiK, and (Tsi)Cl2SiLi were 106, 70, and 87 ppm, respectively. Amphiphiles: Halosilylenoids, stable at room temperature (Tsi)X2SiLi (Tsi=C(SiMe3)3, X=Br, Cl; see scheme), were synthesized from the reaction of TsiSiX3 with lithium naphthalenide. These compounds showed nucleophilic and amphiphilic properties in their reaction with alcohols, MeI, and 2,3‐dimethyl‐1,3‐butadiene. The 29Si chemical shifts for (Tsi)Br2SiLi, (Tsi)Br2SiK, and (Tsi)Cl2SiLi were 106, 70, and 87 ppm, respectively.