Synthesis of halo-fluoro-substituted adamantanes by electrophilic transannular cyclization of bicyclo[3.3.1]nonane dienes

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

“…In the 19 F NMR spectrum of 2 the typical appearance of the AB 4 -spin system for the SF 5 -substituent was observed with nine lines for the apical fluorine atom (A-part) at 85.1 ppm and a doublet of multiplets of the basal fluorines (B 4 -part) at 69.4 ppm (J = 143.0 Hz). The characteristic signals of adamantanes 3 and 4 in NMR spectra { 1 H NMR: 3 (s, 3.28 ppm CH 2 Cl), 4 (s, 3.32 ppm CH 2 Cl) and 19 F NMR 4 (s, À133.8 ppm the fluorine atom in the bridgehead position)} are in agreement with those reported for 3 [40] and 4 [28].…”

“…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.…”

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

“…Adamantyl and noradamantyl moieties are often used as the building blocks for new drugs with antiarrhythmic, hypoglycemic, antiviral and other types of physiological activity [11][12][13][14][15]. 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 or radical agents [16][17][18][19][20][21][22][23][24]. It has been shown previously, that transannular cyclizations of polyunsaturated bicyclo[3.3.1]nonane derivatives with electrophiles (iodine, bromine, acids, NHlgS (Hlg = Cl, Br, I), 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)) [16][17][18][19][20] lead to adamantane derivatives.…”

“…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 or radical agents [16][17][18][19][20][21][22][23][24]. It has been shown previously, that transannular cyclizations of polyunsaturated bicyclo[3.3.1]nonane derivatives with electrophiles (iodine, bromine, acids, NHlgS (Hlg = Cl, Br, I), 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)) [16][17][18][19][20] lead to adamantane derivatives. In contrast, noradamantane, and adamantane derivatives, are formed in the reactions with radical agents (CCl 4 /AIBN, CHCl 3 /g-irradiation, C 6 H 5 SH, CH 3 PhSO 2 Hlg (Hlg = Cl, Br)) [21][22][23][24].…”

“…After the reaction of 1 with ICF 2 PO(OEt) 2 and copper traces of HCF 2 PO(OEt) 2 were found (<1%, 19 F NMR of the reaction mixture (CDCl 3 ): À138.2 ppm, dd, 2 J F,P = 90.0 Hz, 2 J F,H = 48.0 Hz). Similar formation of reduced byproducts was reported earlier [31].…”