Fuerstner, Alois published the artcileCyclobutenes by Platinum-Catalyzed Cycloisomerization Reactions of Enynes, Quality Control of 69626-75-1, the publication is Journal of the American Chemical Society (2005), 127(23), 8244-8245, database is CAplus and MEDLINE.
1,6-Enynes bearing (electron-rich) aryl substituents on their alkyne moiety rearrange to cyclobutene derivatives in the presence of catalytic amounts of PtCl2 in toluene. The reaction is significantly accelerated when performed under an atm. of CO (1 atm), most likely by increasing the electrophilicity of the metal template by temporary coordination to this π-acidic ligand. This transformation allows the build up of considerable strain in the products as witnessed by the productive formation of tricyclic skeletons, such as 7 or 9. Moreover, these products provide evidence for the mechanistic scenario of platinum-catalyzed cycloisomerization reactions previously proposed, which are thought to proceed via organo-platinum species that mimic the reactivity of metal-complexed “nonclassical” carbocations.
Journal of the American Chemical Society published new progress about 69626-75-1. 69626-75-1 belongs to benzofurans, auxiliary class Iodide,Benzofuran, name is 2-Iodobenzofuran, and the molecular formula is C8H5IO, Quality Control of 69626-75-1.
Referemce:
https://en.wikipedia.org/wiki/Benzofuran,
Benzofuran | C8H6O – PubChem