Primary Vinyl- and Alkynylstibines: Preparation and Characterization
Résumé
Primary unsaturated stibines ethenylstibine (la), E-prop-1-enylstibine (1b), ethynylstibine (2a), and prop-1- ynylstibine (2b) are synthesized by reaction of antimony trichloride with the corresponding vinyltributylstannanes 3a,b and alkynyltributylstannanes 4a,b, respectively, followed by a chemoselective reduction of the formed dichlorostibines Sa,b and 6a,b. Compounds la,b and 2a,b are characterized on the basis of spectral data (NMR, photoelectron spectroscopy and high resolution mass spectrometry). In particular, the PE spectra display very well-resolved bands (1a, 9.3, 10.3, 11.2, 11.9, 13.7, and 15.0 eV; 2a, 9.7, 10.5, and 11.2 eV). The α-unsaturated stibines exhibit a low stability at room temperature even in the presence of a solvent (τ1/2 ca. 1 h) and lead to the formation of oligomeric material or an antimony mirror on the wall of the flask. Attempts to detect C-Sb multiple bond derivatives by a base-catalyzed rearrangement of 1 or 2 were unsuccessful. © 1995, American Chemical Society. All rights reserved.