Photochemistry of Hydrogen Bromide-Acetylene Complexes in Solid Krypton

Article abstract of DOI:10.1021/j100097a017

Hydrogen-bonded complexes between HBr and acetylene in inert gas matrices were subjected to medium-pressure Hg lamp photolysis at 12 K.For HBr-acetylene, the major product was bromoacetylene, while vinyl bromide was present in trace amounts.When HBr-perdeuterioacetylene and DBr-acetylene complexes were photolyzed, bromoacetylene, deuteriobromoacetylene, and the hydrogen exchange product, DBr(HBr)-C2HD, were the primary products.Partially deuterated vinyl bromides were present in trace amounts.In HBr-perdeuterioacetylene, the only isomer observed was cis-CDBr=CHD.In DBr-acetylene, both cis- and trans-CHBr=CHD were observed.In neither experiment was the 1,1-addition product formed.The results are interpreted in terms of the supramolecule model of complex photochemistry put forth by Abrash and Pimentel.