MBH reaction mechanism

The new kinetic evidence just discussed has also stimulated further theoretical studies on the MBH reaction mechanism [10,11]. These studies suggest that step IV can occur via two pathways (Scheme 3.5) (a) in the absence of a proton source, elimination is assisted by a second molecule of aldehyde (14), as proposed by McQuade, or (b) in the presence of a proton source, such as an alcohol, the elimination proceeds via intermediate 16 or a similar species. 

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