Tentative hydrolysis mechanism

Figure 3. Tentative hydrolysis mechanism of different xylans by the xy-lanolytic enzymes of T. rtesei.

Mass spectrometry has also been used to characterize organostannoxanes of the type Me2Sn(Cl)0C(0)CF3 and their products of hydrolysis . The base peak in all cases has been tentatively assigned to the CF30Sn+ ion but the mechanism leading to this rearrangement has not been explored in detail. 

Because detailed mechanistic information is not available, a tentative mechanism is proposed here. It is assumed that iodine first adds to the double bond to form an iodonium cation in a process similar to the bromination of alkene, then nucleophilic attack from acetate leads to the formation of the ra/25 -o -iodoacetate. In the presence of silver acetate, a-iodo leaves to give a dioxoanyl carbocation, which is attacked by the second acetate anion to give 1,2-diacetate. Upon hydrolysis or LiAlH4 reduction, diacetate is transformed into trans-l,2-diol. The displayed mechanism is similar to the one proposed by Sudalai. ... 

Hydrolysis and Other Reactions.—Continuing earlier studies Bull. Chem. Soc. Japan, 1976, 49, 1059), Japanese workers have now examined the hydrolysis of sucrose solubilized in benzene by a reversed micelle formed from dodecyl-benzenesulphonic acid. An enhancement factor of 400 (relative to aqueous hydrochloric acid) was observed, while ethanesulphonic acid showed only slight effect. It was tentatively concluded that the enhancement is related to the formation and stability of reversed micelles. Other workers have examined the acid-catalysed hydrolysis of sucrose at different hydrochloric acid concentrations and postulate a change of mechanism at 5.68 mol 1. ... 

There has recently been much interest around proton conduction in condensed phosphates. Lanthanum metaphosphate (La(P03)3) exhibits a modest proton conductivity [59] whereas diphosphates of tetravalent metals, e.g., SnP207 and TiP207, appear to exhibit a high proton conduction peak at intermediate temperatures (around 200°Q. The effect is reportedly enhanced by substituting In for the tetravalent cation, and the conductivity can exceed 0.1 S/cm [60]. It is uncertain what is the defect or doping mechanism behind these behaviors. The same materials exhibit a lower, temperature-dependent conductivity above 400°C, tentatively attributed to protons from hydrolysis of the diphosphate groups [61]. 

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