Conditions for and Features of SN Reactions with Neighboring Group Participation

1 Conditions for and Features of SN Reactions with Neighboring Group Participation 

Because of this neighboring group participation, a cyclic and possibly strained (depending on the ring size) intermediate A is formed from the alkylating agent  

The range of possible neighboring group participations mentioned above reflects the usual ring closure rates of five-membered three-membered six-membered other ring sizes. 

In general, one speaks of a neighboring group effect only when the cyclic and usually positively charged intermediate cannot be isolated but is subject to an SN2-like ring opening by the 

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