Crotonaldehyde Formation from Decomposition of ICH₂CH₂OH on Powdered TiO₂

Abstract

Adsorption and reactions of 2-iodoethanol on TiO(2) have been studied by Fourier transform infrared spectroscopy. ICH(2)CH(2)OH possesses two reactive centers of C-I and C-OH. It is found that its decomposition leads to the formation of crotonaldehyde on TiO(2). A reaction sequence of ICH(2)CH(2)OH --> ICH(2)CH(2)O- --> CH(3)CHO --> CH(3)CH=CH-CHO is proposed. Although the decomposition routes of C(2)H(5)OH and C(2)H(5)I, both forming C(2)H(5)O- on TiO(2), suggest that -OCH(2)CH(2)O- may play a role in the crotonaldehyde formation, reaction of HOCH(2)CH(2)OH on TiO(2) shows that this is not the case. Adsorbed H(2)O is formed in the ICH(2)CH(2)OH decomposition on TiO(2); however, it is found that ICH=CH(2), possibly generated by ICH(2)CH(2)OH dehydration, is not important in the crotonaldehyde formation.