Trimethylsilyl Trifluoromethanesulfonate Mediated Synthesis Of 6-substituted Decaboranyl Ethers And Sulfides

Borane generally refers to borohydrides and its derivatives composed of boron and hydrogen.Since borane was first reported by Stock in 1912,borane has attracted great interest among boron chemists due to its unusual multicenter bonding pattern and wide range of applications.Since the 1950s,boron chemists have gradually gained a systematic understanding of the synthesis,properties and applications of polyhedral boranes.Especially in recent years,the upsurge of research on BNCT is urgently needed to develop new methods for synthesizing various functionalized polyhedral boranes.In the development of synthetic chemistry of polyhedral boranes,decaborane(14)and its derivatives have been widely used as starting materials for the synthesis of numerous polyhedral boranes and carboranes.However,due to its few types and defects in synthetic methods,this limits the development of polyhedral boranes in various fields to a certain extent.Therefore,the development of a simple and efficient synthesis method of polyhedral borane has important theoretical significance and practical value for the development of borane chemistry.In this thesis,a new synthesis method was developed.Different from the traditional method that requires strong acid protons to activate closo-[B10H10]2-we use trimethylsilyl cations as an activator,non-polar solvent hexane as the solvent for the reaction,when the system contains alcohols or phenols,we can obtain alkyl or phenyl decaboranyl ethers;when the system contains H2O,we get trimethylsilyl decaboranyl ethers;when the system contains thiols or thiophenols,We got decaboranyl sulfides that had never been reported before.This reaction has high regional selectivity,producing a single B(6)region isomer in all cases.For simple borane anions such as BH4-and B3H8-,TMS+ can abstract a negative hydrogen on boron to generate BH3 and B3H7.Since BH3 and B3H7 are typical electron-deficient compounds,they cannot exist stably.It will form Lewis acid-base adducts with strong coordinating solvents in the system,namely L·BH3 and L·B3H7.