Hydrolysis of acetals and ketals

Lipshutz BH, Harvey DF (1982) Hydrolysis of acetals and ketals using lithium tetrafluoroborate. Synth Commun 12 267-277... 

Deiodination (see Reduction reactions) Deketalization (see Hydrolysis of acetals and ketals)... 

Acid acts as a catalyst both for the formation and the hydrolysis of acetals and ketals, so to synthesise ketals and acetals in good yield, of the favourable conditions are the reaction is carried out in the absence of water using a small amount of concentrated sulphuric acid or an organic acid like para-toluenesulphonic acid. The yields are further boosted if the water formed during the reaction is removed from the reaction mixture. 

P. Deslongchamps, Y. L. Dory, and S. Li, 1994 R.U. Lemieux award lecture hydrolysis of acetals and ketals. Position of reaction states along the reaction coordinates, and stereoelectronic effects, Can. J. Chem., 72 (1994) 2021-2027. 

Intermolecular general acid catalysis of the hydrolysis of acetals and ketals Fig. 8 shows, in general terms, the reaction profile for the specific acid-catalysed hydrolysis of an acetal or a ketal. 

The reductive cleavage of methyl glycosides has some analogy with the hydrolysis of acetals and ketals [92]. Since glycosides are acetals, then formation of an oxocarbenium ion in the course of both reactions may imply mechanistic similarities. An A-2 mechanism has been suggested for hydrolysis of methyl (or phenyl) D-glycopyranosides [93]. According to this mechanism for the hydrolysis of... 

The regiochemical outcomes of Brpnsted acid-catalyzed reactimis of carbohydrate derivatives have been studied in detail, particularly in the context of the selective formation or hydrolysis of acetals and ketals [6, 7]. The group of Nagorny has added a new dimension to this strategy by employing chiral Br0nsted acids for the selective formation of mixed acetals and ketals from pyranoside-derived 1,2-diol... 

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