• In the third step, a fragmentation reaction occurs to formed CO₂, CO and Cl^-. This is very entropically favoured.
• A sulphur ylide is formed in the second to last step of this reaction. This compound is also formed in the Kornblum reaction.
• This reaction is particularly effective when using primary alcohols.
• Other reactions involving sulphur reactivity: Kornblum, Mannich, Paal-Knorr Thiophene Synthesis, Pummerer and Ramburg-Backlund reactions.


References:

• Kwok Wai Choi M.; Toy P.H.; Tetrahedron, 2003, Volume 59, Issue 36, 7171-7176
• Richardson S.K.; Ife R.J.; Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry, 1989, Issue 6, 1171-1174