title: Two types of intramolecular homolytic substitution reactions at group XIV atoms: unusual radical 1,4-Sn shifts from Si to C and carbonylative SHi reaction at Si.
abstract: 4-[(Trimethylstannyl)diphenylsilyl]butanoyl radical, arising from the corresponding 3-(stannylsilyl)propyl radical and CO, undergoes an SHi reaction at Si with extrusion of trimethyltin radical to give silacyclopentanone. The parent 3-(stannylsilyl)propyl radical was also found to isomerize to (3-stannylpropyl)silyl radical via a 1,4-Sn shift from Si to C with a rate constant of 9.3 x 10(4) s-1 at 80 degrees C. Ab initio and DFT MO calculations support a front-side attack mechanism.
authors.affiliation: Fachbereich Chemie, Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany. studer@Mailer.Uni-Marburg.de
authors.forename: Armido
authors.initials: A
authors.lastname: Studer
authors.forename: Stephan
authors.initials: S
authors.lastname: Amrein
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsubara
authors.forename: Carl H
authors.initials: CH
authors.lastname: Schiesser
authors.forename: Takashi
authors.initials: T
authors.lastname: Doi
authors.forename: Tomonori
authors.initials: T
authors.lastname: Kawamura
authors.forename: Takahide
authors.initials: T
authors.lastname: Fukuyama
authors.forename: Ilhyong
authors.initials: I
authors.lastname: Ryu