Ozonolysis - UCLA Chemistry and Biochemistryharding/summaries/14D24.pdf · Ozonolysis: alkene or...
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Ozonolysis: alkene or alkyne is cleaved by reacting it with ozone Example: *Mechanism: O3 ----------> syn addition of O3 Neither Markovnikov nor anti- Markovnikov (O3 is symmetrical) Neither alkene nor O3 is electrophile (both give and receive electrons) ------------> Oxygen lone pairs repel causing molecule to break apart and rearrange (CH3)2S --------> Final stereochemistry: Neither syn nor anti Overall mechanism: Syn addition of O3 ---> Rearrange ---> Add (CH3)2S ---> Final product cleaved by ozone *Useful tip: the products can be found (without going through the mechanism) by slicing the alkene and adding oxygen to the ends of the open alkene
Transcript of Ozonolysis - UCLA Chemistry and Biochemistryharding/summaries/14D24.pdf · Ozonolysis: alkene or...
Ozonolysis:alkeneoralkyneiscleavedbyreactingitwithozoneExample:
*Mechanism:
O3---------->synadditionofO3NeitherMarkovnikovnoranti-Markovnikov(O3issymmetrical)NeitheralkenenorO3iselectrophile(bothgiveandreceiveelectrons)
------------>Oxygenlonepairsrepelcausingmoleculetobreakapartandrearrange
(CH3)2S-------->
Finalstereochemistry:Neithersynnoranti
Overallmechanism:SynadditionofO3--->Rearrange--->Add(CH3)2S--->Finalproductcleavedbyozone*Usefultip:theproductscanbefound(withoutgoingthroughthemechanism)byslicingthealkeneandaddingoxygentotheendsoftheopenalkene
WorksCited
Hardinger,Steven.“Chemistry14DLectureSupplement”4thEd.HaydenMcNeil.2016.Print.