IR spectra of catalysts and adsorbed molecules

1.	At 20–220° on aluminum oxide and NaX, NaY, CeNaY, and HY zeolites, aliene isomerizes to methylacetylene; zeolites whose IR spectra are characterized by the presence of absorption bands of the hydroxyl groups (CeNaY, HY) are more active in this reaction.
2.	The thermal dimerization of aliene at 450° proceeds with the formation of 1,2-dimethylenecyclobutane.
3.	The oligomerization of aliene on -allylnickel bromide, applied on aluminum oxide, at 20–180° gives chiefly 1,3-dimethylenecyclobutane, the formation of which evidently proceeds through a four-membered active complex.