The reversible reaction of ethylene with a main group molecule performed by Yang Peng and coworkers in the Power group was recently reported in Science (2009, 324, 1668). It was also highlighted in the same issue (Science, 2009, 324, 1631) and featured by Science News, RSC (Royal Society of Chemistry) and Chemical and Engineering News magazines.

This paper reported the first example of reversible ethylene binding to a heavier group 14 alkyne species ArSnSnAr (Ar = bulky tephenyl ligand) under very mild conditions. This occurs through a [2+2] cycloaddition reaction which is symmetry forbidden for carbon based compounds on the basis of Woodward-Hoffman rules. The ethylene quickly reacted with multiple tin-tin bonded species (dark green color) under ambient conditions (ca. 25 ˚C, 1atm) to form a bridged ethylene complex (amber color). The ethylene is released by applying reduced pressure or gently heating. This reaction is very different from the corresponding reactions of alkynes with olefins which are symmetry forbidden. It opens a chapter in main group element chemistry involving the interaction of main group compounds with small molecules.

Click here for a Youtube video demonstrating this reversible process!!

For the addition information, please check:

http://www.sciencemag.org/cgi/content/full/325/5948/1668?rss=1

http://www.sciencenews.org/view/generic/id/47734/title/The_element_tin_does_what_carbon_will_not

http://www.rsc.org/chemistryworld/News/2009/September/24090904.asp

http://pubs.acs.org/cen/email/html/8739scic4.html