Vasiliy M. Muzalevskiy

Polyfluorinated Ethanes as Versatile Fluorinated C2-Building Blocks for Organic Synthesis

for Organic Synthesis Valentine G. Nenajdenko,*,†,§ Vasiliy M. Muzalevskiy,† and Aleksey V. Shastin†,‡ †Department of Chemistry, Moscow State University, Leninskie Gory, Moscow 119992, Russia ‡The Institute of Problems of Chemical Physics of the Russian Academy of Sciences (IPCP RAS), Chernogolovka, Moscow Region 142432, Russia A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), 119991, GSP-1, Moscow, V-334, Vavilova St. 28, Russia

Fragmentation of Trifluoromethylated Alkenes and Acetylenes by N,N-Binucleophiles. Synthesis of Imidazolines or Imidazolidines (Oxazolidines) Controlled by Substituent

The reaction of beta-halogeno-beta-polyfluoromethylstyrenes with N,N- or N,O-binucleophiles leads to unexpected fragmentation products (imidazolines) or to heterocyclization giving CF(3)-substituted imidazolidines (N,N-) and oxazolidines (N,O-) depending on aryl substituent. The scope and the reaction mechanism are discussed.

Radical Nitration-Debromination of α-Bromo-α-fluoroalkenes as a Stereoselective Route to Aromatic α-Fluoronitroalkenes—Functionalized Fluorinated Building Blocks for Organic Synthesis

A new highly efficient method for the synthesis of 2-fluoro-2-nitrostyrenes was described. Radical nitration of readily available 2-bromo-2-fluorostyrenes with Fe(NO3)3·9H2O resulted in the formation of the corresponding α-fluoro-nitroalkenes in isolated yields up to 92%. The reaction proceeded as a nitration-debromination sequence to highly stereoselectively give α-fluoro-nitroalkenes as Z-isomers only. The broad scope of this method was demonstrated. Prepared monofluorinated alkenes were shown to be versatile building blocks for the synthesis of various fluorinated products.

Selective, Metal-Free Approach to 3- or 5-CF3-Pyrazoles: Solvent Switchable Reaction of CF3-Ynones with Hydrazines

A detailed study of the reaction of trifluoroacetylated acetylenes and aryl (alkyl) hydrazines was performed, aimed to the regioselective synthesis of 3- or 5-trifluoromethylated pyrazoles. It was found that the regioselectivity of reaction depends dramatically on the solvent nature. Highly polar protic solvents (hexafluoroisopropanol) favor the formation of 3-trifluoromethylpyrazoles. In contrast, when the reaction was performed in polar aprotic solvents (DMSO), the formation of their 5-CF3-substituted isomers was preferentially observed. Alternatively, the regioselective assembly of 3-CF3-substituted pyrazoles can be performed via two-step one-pot procedure. The reaction of trifluoromethylated ynones with aryl (alkyl) hydrazines in the presence of acidic catalysts leads to formation of the corresponding hydrazones. The latter can be smoothly transformed into 3-CF3-pyrazoles by treatment with a base. This solvent-switchable procedure was used for the preparation of such important drugs as Celebrex and SC-560 as well as their isomers in gram scale. The possible reaction mechanism is discussed.

Chemistry of Fluorinated Indoles

The chapter is devoted to the synthesis and application of indoles as well as some their azaanalogues bearing fluorine atoms, trifluoromethyl groups, and perfluorinated aryl fragments.

Chemistry of Fluorinated Pyrroles

Synthetic approaches towards pyrroles, bearing fluorine atoms and trifluoromethyl group, are overviewed in this chapter. Literature data are surveyed accordingly to reaction type used to obtain the fluorinated pyrrole moiety. Properties as well as some applications of fluorinated are also reviewed.