Interaction of 2,4,6-tris(fluorosulfonyl)chlorobenzene with O-, N-, S-, C-nucleophiles and F-anion Andrey A. Filatov, Vladimir N. Boiko, Yurii L. Yagupolskii * Institute of Organic Chemistry, National Academy of Sciences of Ukraine, 5 Murmanskaya St., UA-02094 Kiev-94, Ukraine 1. Introduction In the frame of our continuous interest to aromatic systems modified by fluorine containing electron withdrawing substituents we would like to attract attention to the accessible, stable and intriguing system of symmetric tris(fluorosulfonyl)benzenes [1,2] as a flat platform for three general pathway designs of various molecules (Picture 1): (1) through nucleophilic attack of SO 2 F function (potentially biologically active sulfamides, netlike polymers, etc.); (2) by mild nucleophilic displacement of activated aromatic halogen (based on easy obtainable 2,4,6-tris(fluorosulfonyl)- benzene chloride 1) with fluorosulfonyl fragments preserva- tion; (3) via combined processes including step by step procedures (heterocyclizations as well as polymerization). Simple and effective preparative synthetic procedures for the syntheses of 2,4,6-tris(fluorosulfonyl)chlorobenzene (1), corre- sponding phenol 2 and aniline 3 have been elaborated and presented in our previous publications [1,2] that made these compounds available for thorough investigations. Above mentioned molecules correspond to the structural analogs of 2,4,6-tris(trifluoromethylsulfonyl)benzene derivatives which were previously studied by our group in detail [3–5], but fluorosulfonyl derivatives are much more accessible. Noteworthy to mention that electronic properties of the SO 2 F group (s p 1.01) are similar to SO 2 CF 3 (s p 1.04–1.06 [6,7]). pK a values of above mentioned 2,4,6-three substituted phenols in acetonitrile are close to each other: phenol 2 – 5.53 and 2,4,6-(SO 2 CF 3 ) 3 phenol – 4.79 that outdo the acidity of aromatic sulfonic acids [8,9]. DG acid values of anilines in gaseous phase are: aniline 3 – 307.5 and 2,4,6- (SO 2 CF 3 ) 3 aniline – 304.8 kcal/mol [10]. These facts predict high mobility of chlorine atom in chlorobenzene 1. On the other hand, SO 2 F groups can also react with nucleophilic agents. The last circumstance make it possible to realize a consecutive introduction various fragments into the molecule of 1. As to reactivity of SO 2 F group it is known that fluorosulfo- nylbenzenes react with bases specifically. Appreciable hydrolysis occurs when benzene ring is activated with nitro group or with halogen atom [11]. Reaction rates of p-substituted fluorosulfo- nylbenzenes with benzylamines were in 1000 times [12] and with aniline in five degree less [13] than the rate of chlorosulfonyl- benzenes reactions. Some comparison of fluorosulfonyl aromatic moiety and activated aromatic halogen atom reactivity towards various nucleophilic agents [2,14–16] did not give exact predictions about 2,4,6-tris(fluorosulfonyl)chlorobenzene 1 regioselective behavior in the basic conditions. The later has different electrophilic centers and its reactions with nucleophiles may cause to unexpected but important results. Previously investigated by us chemical reactivi- ty of 1,3,5-tris(fluorosulfonyl)benzene gave no chance to general- ize unambiguously outcome of nucleophilic attack towards this molecule that was strongly dependent on the nucleophile type, its Journal of Fluorine Chemistry 143 (2012) 123–129 A R T I C L E I N F O Article history: Received 27 February 2012 Received in revised form 10 May 2012 Accepted 14 May 2012 Available online 20 May 2012 Keywords: Arenes Sulfonyl fluorides Nucleophilic substitution Synthetic methods A B S T R A C T Reactions of 2,4,6-tris(fluorosulfonyl)chlorobenzene 1 with O-, N-, S-, C-nucleophiles and F-anion showed high reactivity of 1 that was defined by three strong electron withdrawing SO 2 F groups creating several electrophilic centers within the molecule. Conditions for selective chlorine atom substitution were defined that resulted in formation of corresponding ethers, amines and sulfides, while excess of nucleophile commonly led to SO 2 F groups implication in the reaction. Two equivalents of fluoride-anion source gave rise not only to the chlorine-fluorine substitution but afforded in the anionic s-complex formation with two fluorine atoms in the hem-position. Reduction of chlorobenzene 1 with zinc/AcOH was found to be a choice for 1,3,5-tris(fluorosulfonyl)benzene preparation. ß 2012 Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +380 44 5590349; fax: +380 44 5732643. E-mail addresses: Yagupolskii@ioch.kiev.ua, gegols@yandex.ru (Y.L. Yagupolskii). Contents lists available at SciVerse ScienceDirect Journal of Fluorine Chemistry jo ur n al h o mep ag e: www .elsevier .c om /loc ate/f luo r 0022-1139/$ – see front matter ß 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jfluchem.2012.05.015