Nicolay Yu. Adonin

A new application of (polyfluoroorgano)trifluoroborate salts: the palladium-catalysed cross-coupling reaction with substituted benzenediazonium tetrafluoroborates

Abstract For the first time (polyfluoroorgano)trifluoroborate salts, namely K[C 6 F 5 BF 3 ], K[C 6 HF 4 BF 3 ] (all three isomers), K[3,4,5-C 6 H 2 F 3 BF 3 ], and K[CF 2 CFBF 3 ] were principally applied as reagents to Pd-catalysed cross-coupling reactions. A series of polyfluorinated biphenyls C 6 H 5− n F n –C 6 H 4 X-4′ were obtained from K[C 6 H 5− n F n BF 3 ] and the substrates [4-XC 6 H 4 N 2 ][BF 4 ] in the presence of Pd catalysts. The influence of the number and the position of the fluorine atoms in the (polyfluorophenyl)trifluoroborate salts on the reactivity in the coupling reaction was elucidated. In addition to (polyfluorophenyl)trifluoroborate salts, the cross-coupling was expanded to a first example of a perfluoroalkenyl reagent. K[CF 2 CFBF 3 ] reacted with [4-FC 6 H 4 N 2 ][BF 4 ] and formed CF 2 CF–C 6 H 4 F-4.

The palladium-catalysed cross-coupling reaction of lithium polyfluorophenyltrimethoxyborates with 4-fluoroiodobenzene

Abstract Li[C 6 F 5 B(OMe) 3 ], Li[C 6 HF 4 B(OMe) 3 ] (all three isomers) and Li[3,4,5-C 6 H 2 F 3 B(OMe) 3 ] are the first examples of polyfluorophenyltrimethoxyborate salts which have been applied as reagents to Pd-catalysed cross-coupling reactions. A series of polyfluorinated biphenyls C 6 H 5− n F n -C 6 H 4 F-4′ were obtained from Li[C 6 H 5− n F n B(OMe) 3 ] and the model substrate 4-FC 6 H 4 I in the presence of Pd catalysts. The influence of the number and the position of fluorine atoms in the polyfluorophenyltrimethoxyborate salts on the reactivity in the coupling reaction was elucidated.

Synthesis and Properties of Perfluoroalkenylboronic Acids and some of their Derivatives

Lithium perfluoroalkenyltrimethoxyborates were prepared and characterised by NMR spectroscopy. These compounds possess the properties inherent in both organic and inorganic boron-containing compounds. Li[XCF=CFB(OMe)3] (X = F, c«-CF3, Irans-CF^) react with I2 to give corresponding 1iodopolyfluoroalkenes in 30-50 % yields. Interaction of Li[XCF=CFB(OMe)3] with ClSiMe3, followed by working up with XCF=CFLi leads to formation of lithium bis(perfluoroalkenyl)dimethoxyborates. Reaction of Li[(XCF=CF)„B(OMe)4-n] with K[HF2] in aqueous HF gives corresponding potassium perfluoroalkenylfluoroborates, K[(XCF=CF)nBF4.n].

Synthesis of Perfluoroalkyl( Methoxy) Borates and - Boranes

Interaction of lithium perfluoroalkyltrimethoxyborates, Li[CnF2n+iB(OMe)3] (n = 3, 4, 6), with CISiMe3 results in formation of the corresponding esters Ο,Κ^+ιΒίΟΜε)^ in 93-95 % yields. They are sufficiently stable both CH2C12 and etherical solvents (ether, THF) and react with C2F5Li to give Li[(C„F2n+i)(C2F5)B(OMe)2]. Metathesis of the latter with KF leads to corresponding potassium salts.

1-Alkyl-3-methylimidazolium 4-organyloxy-2,3,5,6-tetrafluorophenyltrifluoroborates as a new platform for ionic liquids with specific properties

A new synthetic platform for ionic liquids (ILs) with specific properties was suggested based on the polyfluorophenyltrifluoroborate anions, Q[4-XC6F4BF3] (X = F, RO). Convenient preparative approaches to these ILs including the ones with chiral counteranions were developed. The dependence of physicochemical properties of ILs on the nature of substituents in the fluorinated ring was studied.

Substitution of fluorine in M[C6F5BF3] with organolithium compounds: distinctions between O- and N-nucleophiles

Borates M[C6F5BF3] (M = K, Li, Bu4N) react with organolithium compounds, RLi (R = Me, Bu, Ph), in 1,2-dimethoxyethane or diglyme to give M[4-RC6F4BF3] and M[2-RC6F4BF3]. When R is Me or Bu, the nucleophilic substitution of the fluorine atom at the para position to boron is the predominant route. When R = Ph, the ratio M[4-RC6F4BF3]/M[2-RC6F4BF3] is ca. 1:1. Substitution of the fluorine atom at the ortho position to boron is solely caused by the coordination of RLi via the lithium atom with the fluorine atoms of the BF3 group. This differs from the previously reported substitution in K[C6F5BF3] by O- and N-nucleophiles that did not produce K[2-NuC6F4BF3].

Synthesis and Structural Features of Nanostructured Cuprous Chloride with High Catalytic Activity

A method for nanostructured cuprous chloride preparation by reductive thermolysis of a CuCl2⋅2H2O and Cu(OH)2 mixture in glycerol has been developed. The resultant CuCl was characterized with infrared spectroscopy, X-ray photoelectron spectroscopy, EXAFS spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The prepared samples of CuCl demonstrated high catalytic activity in the “direct synthesis” of triethoxysilane.