Intercepting the Disilene‐Silylsilylene Equilibrium. Issue 5 (3rd January 2019)

• Record Type: Journal Article
• Authors: Stanford, Martin W.; Schweizer, Julia I.; Menche, Maximilian; Nichol, Gary S.; Holthausen, Max C.; Cowley, Michael J.
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 5(2019)
• Page Start: 1329
• Page End: 1333
• Publication Date: 2019-01-03
• Subjects: disilenes -- mechanism -- silicon chemistry -- silylenes; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201810056
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The equilibrium between disilenes (R2 Si=SiR2 ) and their silylsilylene (R3 Si−SiR) isomers has previously been inferred but not directly observed, except in the case of the parent system H2 Si=SiH2 . Here, we report a new method to prepare base‐coordinated disilenes with hydride substituents. By varying the bulk of the coordinating base and other silicon substituents, we have been able to control the rearrangement of disilene adducts to their silylsilylene tautomers. Remarkably, 1, 2 migration of a trimethylsilyl group is preferred over hydrogen migration. A DFT study of the reaction mechanism provides a rationale for the observed reactivity and detailed information on the bonding situation in base‐stabilized disilenes. Abstract : The isomerization of disilene, Si2 H4, to its silylsilylene tautomer occurs readily. Stable disilenes with bulky substituents display reactivity that indicates the same rearrangement can occur, but experimental observations of the silylsilylene isomers are rare. The base coordinated hydridodisilenes that rearrange to their silylsilylene isomers are reported, together with a detailed mechanistic study of the transformation.