Iodine-Catalyzed Selective Functionalization of Ethane in Oleum: Toward a Direct Process for the Production of Ethylene Glycol from Shale Gas

Abstract

Direct valorization of ethane, a substantial component of shale gas deposits, at mild conditions remains a significant challenge, both from an industrial and an academic point of view. Herein, we report iodine as an efficient and selective catalyst for the functionalization of ethane in oleum at low temperatures and pressures. A thorough study of relevant reaction parameters revealed iodine to be remarkably more active than the previously reported “Periana/Catalytica” catalyst under optimized conditions. As a result of a fundamentally different catalytic cycle, iodine yields the bis-bisulfate ester of ethylene glycol (HO3SO–CH2–CH2–OSO3H, EBS), whereas for state-of-the-art platinum-based catalysts ethionic acid (HO3S-CH2–CH2–OSO3H, ETA) is obtained as the main product. Our findings open up an attractive route for the direct conversion of ethane toward ethylene glycol.

Electrocatalytic Oxyesterification of Hydrocarbons by Tetravalent Lead

“…The arguably best Pt­(II) catalysts were significantly improved by use of SO 3 as oxidant with the added advantage of the formation of bisulfate salts stable to further oxidation . Oxidation of light alkanes has also been demonstrated using high-valent iodine compounds . Electrocatalytic transformations are now very much in the vogue, leading to several reports on the anodic oxidation of aliphatic and aromatic hydrocarbons. , There is also a notable example for the use of electrochemically generated active Pd species for the oxidation of methane to a mixture of methyl bisulfate and methyl sulfonate …”