Facile insertion of ethylene into a group 14 element-carbon bond: effects of the HOMO–LUMO energy gap on reactivity

Abstract

The diarylstannylenes, Sn(Ar^iPr4)₂ and Sn(Ar^iPr6)₂, (Ar^iPr4 = C₆H₃-2,6-(C₆H₃-2,6-ⁱPr₂)₂, Ar^iPr6 = C₆H₃-2,6-(C₆H₂-2,4,6-ⁱPr₃)₂), undergo a facile migratory insertion reaction with ethylene at 60 °C to afford the alkyl aryl stannylenes Ar^iPr4SnCH₂CH₂Ar^iPr4 and Ar^iPr6SnCH₂CH₂Ar^iPr6 which were characterized via¹H, ¹³C and ¹¹⁹Sn NMR, UV-vis and IR spectroscopy, as well as by X-ray crystallography. Quantum mechanical calculations were performed, and two potential mechanisms were identified, with a migratory insertion reaction pathyway being energetically preferred.