Acetoxylation in Organic Synthesis

Acetoxylation is a valuable method for the introduction of an OH group into organic compounds, which can be used for further syntheses. In Section 3.3.14.2 it has been mentioned that acetoxylation of higher and cyclic olefins with palladium salts, or catalyzed by palladium salts or metal, mostly leads to allylic derivatives. This also takes place in the catalytic acetoxylation of terpenic olefins [79, 80]. 

In the presence of nitrates [4, 81], palladium nitro complexes [5, 31], and with different oxidants, glycol derivatives are produced according to eq. (23)  

In the presence of LiCl, palladium acetate catalyzes the regio- and stereospecific 1,4-acetoxychlorination of linear and cyclic 1,3-dienes. The oxidant is benzo-quinone (eq. (24)) [89]. 

Examples of the use of 1,4-addition products in organic synthesis have been given by Backvall [90, 91]. 

Acetoxylation of aromatics (eq. (25)) was first carried out by Davidson and Triggs [92] to produce phenyl acetate, which could give rise to the development of a new phenol synthesis. The formation of phenyl acetate is accompanied by the formation of biphenyl (see Section 3.3.14.7.2). In the presence of oxidants such as Pb(OAc)4, NaN02, NaNOs, KMn04, K2CrOv [93] and P-Mo-V heteropolyacids [94], phenyl acetate is the main product. The favored ring acetoxylation with high-oxidation-state Pd catalyst over dimerization with low-oxidation-state catalyst has recently been confirmed [95]. With toluene, probably in an allylic-like oxidation, benzyl acetate is obtained [92]. 

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