Synthesis of Tetraphenylstannacyclopentadienes (Stannoles). I. Alkylation of 1,1-Dihalostannoles Leading to Lithium 1,1-Di-h1-cyclopentadienyl-1-halo-2,3,4,5-tetraphenylstannole, an (R4SnX)-Anion with Pseudorotating Axial- and Equatorial-Fluxional h1-Cyclopentadienyl Groups.
Abstract
1,1-Dibromo- and 1,1-diiodo-2,3,4,5-tetraphenylstannacyclopentadiene (dibromo- and diiodostannole) formed from controlled phenyltin cleavage of hexaphenylstannole by elemental bromine and iodine, respectively, undergo conventional alkylation by methyllithium to form the expected 1,1-dimethylstannole, but treatment with excess lithium or thallium cyclopentadiene yields cubic crystals whose analytical data agree with the formulation X(C5H5)2SnC4(C4H5)4M where X=Br, M=Li, Tl and where X=I, M=Li. Infrared nu asym and nu sym (Sn-Br) absorptions in the starting dibromostannole are replaced by a single feature at 225/cm in the X=Br products, and absorptions in the 3000 and 1595-695 cm(-1) region specify the h(1)-cyclopentadiene nature of the C5H5Sn unit. Only slight broadening of the fluxional C5H5 resonances is observed on cooling to -100 C however, the two resonances of equal intensity undergo reversible collapse to a single, unshifted peak at 90 deg for X=Br and 100 C for X=I.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1981
- Accession Number
- ADA102604
Entities
People
- Jerold J. Zuckerman
- L. M. Principe
- W. -z. Min Rhee
- W. A. Gustavson
Organizations
- University of Oklahoma