Metal and Boron Derivatives of Fluorinated Cyclic 1,3-Dicarbonyl Compounds

Abstract

Starting from the corresponding cyclic 1,3-diketones or other precursors (cyclic ketones as well as lactones), several new salts and chelate complexes of fluorinated 1,3-dicarbonyls were obtained. Their preparative significance was demonstrated by straightforward syntheses of fluorinated pyrazoles, benzimidazoles and 1,7-ketoesters. The structure of a boron chelate of 2-(trifluoroacetyl)-cyclohexanone was investigated by X-ray diffraction.

Synthesis of mononuclear and dinuclear palladium (II) complexes containing oxadithioether ligands and their catalytic activities in norbornene polymerization

“…The NMR data were assigned to “L n Pd(F·BF 3 )” species and BF 2 (acac) by comparison with values in the literature. [ 92–95 ] Observation of the signals from BF 2 (acac) suggests the formation of dicationic palladium species (see Figure S53, SI) and, in our opinion, presents a catalyst deactivation pathway that occurs in the catalyst systems under study. It should be noted that the significant decrease in activity of the monuclear complexes compared with the dinuclear complexes (e.g., 4a , 6a vs 4b , and 6b ) can also be explained by metal–metal cooperativity effect, which was reported by C. Chen et al [ 96–98 ] in ethylene polymerization by dinuclear α‐diimine Ni (II) and Pd (II) complexes.…”

Chemistry of fluoro-substituted β-diketones and their derivatives

“…74 ± 76 Similarly, the reactions of Cu(II) and Ni(II) acetates with 2-polyfluoroacylcycloalkanones 22 in diethyl ether afford cyclic fluorinated b-diketonates 46 (yields 42% ± 100%). 77 The reactions of boron trifluoride etherate with trifluoromethyl-1,3-diketones 21 78 and 2-trifluoroacetylcyclohexanone (22a) 77 Lithium salts of acyclic fluoro-substituted b-diketones 50 were obtained by both the reaction of lithium hydroxide monohydrate with the corresponding 1,3-diketone 21 79,80 and the modified Claisen condensation.…”

“…81 ± 83 Cyclohexanone also reacts with fluorocarboxylates in the presence of LiH and NaOMe, which is an alternative approach to the synthesis of lithium and sodium 2-polyfluoroacylcyclohexanonates (49), respectively. 77,83 The literature data on the structures and the methods for the synthesis of fluoroalkyl-containing lithium 1,3-diketonates 49 and 50 are summarized in a recent review. 83 It is noteworthy that fluorinated lithium 1,3-diketonates are valuable and convenient synthons.…”

“…77, 82, 84 ± 91 In addition, lithium complexes of fluoro-substituted b-diketones are not only synthetic equivalents of the corresponding dicarbonyl compounds, but offer wider opportunities to their use. 77 …”

Reactions of fluoroalkyl-containing lithium 1,3-diketonates with diaminoarenes and 2-aminobenzenethiol

“…9 The reaction of diketonate 1f containing the cyclohex anone moiety with 1,2 diaminobenzene is accompanied by the ring opening and the formation of 2 (6 oxo 7,7,7 trifluoroheptyl)benzimidazole hydrate 6 (see Scheme 1, Table 1). 20 The opening of the cyclohexanone ring was observed in the reactions of 2 (polyfluoroacyl)cyclo hexanones with 1,2 diaminoarenes under the same condi tions, as well as after the treatment of 1 [N (2 amino phenyl)amino] 2 trifluoroacetylcyclohexene with a mix ture of AcOH and HCl, which afforded 2 (6 oxo 7,7,8,8,9,9,10,10,11,11,12,12,12 tridecafluorododecyl) benzimidazole and 2 (6,6 dioxy 7,7,7 trifluoroheptyl) benzimidazole, respectively. 8, 9 11 Hydroxy 4 trifluoroacetyl 11 trifluoromethyl 1,2,3,4,10,11 hexahydro 5H dibenzo[b,e][1,4]diazepine (8) and 1,3 dihydrospiro[benzimidazole 2,1´ cyclohex ane] (9) were isolated in 10% and 24% yields, respectively, as the reaction products of enolate of the trifluoroacyl derivative of diketonate 1f (triketonate 7) with 1,2 di aminobenzene (Scheme 2).…”