Stereochemistry of reaction of thionyl chloride and phosphorous pentachloride with alcohol [closed]








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When a secondary alcohol reacts with SOCl2 (or even PCl5), does the reaction proceed via SN2 or SNi?




For SOCl2 it depends on the reaction conditions- if a base such as pyridine is present the reaction goes with inversion, in the absence of base it goes with retention


Full explanation  [here](https://www.masterorganicchemistry.com/2014/02/10/socl2-and-the-sni-mechanism/)


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