Mi permutation

Likewise, the stereochemistry of free-radical Arbuzov reaction of MeaN with cis/trans 5- and 6-membered benzyl phosphites failed to reveal any evidence of such an Mi permutation (20 21). 

In Figure 3 is pictured the formation of intermediate 22 in a manner analogous to that proposed for the oxidation and Arbuzov reactions. Subsequent Mi permutation places the leaving group in the apical position. Departure of Y then is predicted to yield product with retention of configuration at phosphorus. 

Figure 3, Potential effect of Mi permutation on substitution stereochemistry...

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