Experimental and theoretical studies on the transannular cyclizations of 3,7-dimethylenebicyclo[3.3.1]nonane with polyfluoroalkyl radicals

Elemental F2 with Transannular Dienes: Regioselectivities and Mechanisms

“…Such a set of products unequivocally evidences for the electrophilic addition mechanism as differently substituted double bonds are not discriminated. Such selectivities are in sharp contrast with those observed for the reactions of 1 a and 1 b with perfluoroalkyl radicals20c or neutral electrophiles20a and are in accord with computed model reaction of 1 a with the F + ⋅⋅⋅ H 2 O complex (Figure 4).…”

“…Fortunately, compound 1 allows us distinguish between the radical and non‐radical addition modes because the reaction of 1 with radicals gives noradamantane derivatives predominantly,20c, 21b in contrast to the reactions with electrophiles that lead to substituted adamantanes 21a. 23 We found that this is indeed true for treatment of 1 with the F radical (Figure 3).…”

The reactions of 3,7-dimethylenebicyclo[3.3.1]nonane, norbornadiene and cis,cis-1,5-cyclooctadiene with pentafluoro-λ6-sulfanyl chloride

“…Using the DFT method, we have established that formation of noradamantane derivatives at cyclization of diene 1 with electrophilic trifluoromethyl radical corresponds to kinetic control [31]. This allowed us to assign of noradamantane product 2 forming through the radical mechanism.…”

“…It has been previously shown, that transannular cyclization of bicyclo[3.3.1]nonane dienes with radical agents (CCl 4 /AIBN [29], C 6 H 5 SH, CH 3 PhSO 2 Hlg (Hlg = Cl, Br) [30]) and with polyfluoroalkyl radicals [31] gives mainly noradamantane derivatives. Using the DFT method, we have established that formation of noradamantane derivatives at cyclization of diene 1 with electrophilic trifluoromethyl radical corresponds to kinetic control [31].…”

“…Convenient and selective preparations of functional derivatives of adamantane and noradamantane are based on transannular cyclizations of bicyclo[3.3.1]nonane dienes with electrophilic [24][25][26][27][28] or radical agents [29][30][31]. The transannular cyclizations of norbornadiene with electrophilic and radical reagents [32][33][34][35][36] are used for selective preparation of nortricyclane derivatives.…”