Organolithium reagents reaction with oxiranes

Organolithium reagents reaction with imidothioesters 114 reaction with isothiocyanates 42 reaction with non enethiolizable dithioesters 98 Orthotrithioesters 79 cleavage of 79 reaction with ketones 137 Oxathiane Eliel reagent 19 Oxaziridines as oxidising reagents 27 Oxiranes... 

Early work has shown that the reaction of simple organolithium reagents with oxiranes lead mainly to products from a- or -deprotonation and not from the desired ring opening reaction. However, some reactions of methyllithium , aUyllithium , aryllithiums" , and vinyllithium/potassium reagents " with oxiranes are reported (Scheme 36). 

Some reports concerning the reaction of lithiated thioallylethers with oxiranes have been published. A slow reaction was observed with a terminal oxirane. However, with cyclopentadiene oxide, the reaction occured smoothly with an excellent regioselectivity in favor of the Sjv2 displacement in the ally lie position. Other examples involving sulfur, selenium and silicon stabilized organolithium reagents have been reported . 

Organolithium compounds are less reactive than lithium organocuprates. A number of publications deal with the differences observed between the two reagents in the ring-opening reaction of oxiranes. The reaction of 1,3-cyclohexadienemonooxirane with methyllithium is seen in Eq. 277. ... 

Derivatives of azete are only known as unstable reaction intermediates. Oxetane and azetidine are considerably less reactive than their three-membered connterparts (oxetane reacts with hydroxide anion 10 times more slowly than does oxirane), but nonetheless do undergo similar ring-opening reactions, for example oxetane reacts with organolithium reagents in the presence of boron triflnoride, or with cuprates, and azetidine is opened on heating with concentrated hydrochloric acid. Azetidininm ions react mnch more easily with nucleophiles. ... 

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