Boron trifluoride organolithium reactions

CH20. The dinitroso derivative 77c was converted into the amine 12b in high yield upon treatment with CuCl/HCl (57JCS2888). Metallation of 1 with -BuLi in the presence of boron trifluoride etherate afforded an organolithium TB functionalized at a benzylic methylene position. Subsequent reaction with electrophiles furnished alkylation products 78 without loss of stereochemical integrity (96TL6267, 00TA2875). 

Derivatives of azete are only known as unstable reaction intermediates. Oxetane and azetidine are considerably less reactive than their three-membered counterparts (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 trifluoride, or with cuprates, and azetidine is opened on heating with concentrated hydrochloric acid. 

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