Nucleophilicity and LG Scales

SCHEME 7.3 General fragmentation model of the electrophile-nucleophile pair. LG, PG, and N stand for leaving group, permanent group, and nucleophile. Adapted with permission from Ormaziibal-Toledo et al. [18]. (2013) American Chemical Society. 

The LG abilities in S Ar are difficult to analyze using the method presented earlier. The reason is simple according to Stirling s principle, the study of a local property must be made at the stage of reaction where the LG participates [62]. In round words, the LG ability may be observed in an advanced step of the reaction prior to the formation of the MC. To do this, a quasistatic analysis is 

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