Hydrogen atom transfer between enantiomers of rac-1-phenylethanol

[![HAT & DKR](https://i.stack.imgur.com/ExfKQ.png)](https://i.stack.imgur.com/ExfKQ.png)


(Taken from *Dalton Trans.*, **2012,** *41,* 13423–13428. [DOI:10.1039/c2dt31781h](http://doi.org/10.1039/c2dt31781h))


I have difficulties understanding the hydrogen transfer in the image above. I always thought that hydrogen transfers followed the following formula:


$$\ce{X^. + H-Y -> X-H + Y^.}$$


I can't really see the connection between the picture and the formula. Is it the whole ethanol group that is transferred?




Did you continue reading the paper? :) The source is important and is what was needed to answer the question!


I'm just going to quote from it.



> 
> In DKR [dynamic kinetic resolution] a chemical catalyst is added in order to racemize the enantiomers, ensuring that all the substrate can be utilized. [...] Highly successful catalysts are often Ru(II) complexes [...] The metal complex catalyses racemization by a hydrogen transfer mechanism (Scheme 2).
> 
> 
> 


[![enter image description here](https://i.stack.imgur.com/jENE5.png)](https://i.stack.imgur.com/jENE5.png)


So, the supposed hydrogen transfer occurs via coordination to a metal, followed by β-hydride elimination. Readdition of the metal hydride across the opposite face of the resultant ketone (acetophenone in this case) produces the other enantiomer.


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