Effects of ionized cyclodextrin on decomposition of allyl isothiocyanate in alkaline solutions.

The secondary hydroxyl ion (alkoxide) ion for cyclodextrin (CD) may affect the decomposition of allyl isothiocyanate (AITC) in alkaline solutions. The equilibrium and kinetic parameters involved in the reaction processes were measured. It was found that the interaction between the alkoxide ion for CD and the included AITC occurred more than pKa 12.7. From the identified kinetic parameters and discussion, it was suggested that the reaction site of AITC was located in the vicinity of one of the secondary hydroxyl groups of CD in the cavity.