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The title new compounds are screened for their in vitro antioxidant activity and demonstrated a marked capacity for iron binding.

The compounds (III) and (V) are tested for their potential in vitro antioxidant activity and the compound (IIId) shows best activity for iron binding.

Methyl hypofluorite (CH 3 OF) has been prepared by the reaction of elemental fluorine with methanol in acetonitrile or propionitrile at low temperature. It was removed from the reaction mixture in a stream of nitrogen and purified by fractional distillation. The compound is moderately long-lived, although the liquid has exploded upon rapid warming. The liquid compound has a freezing point of about −142°C, and vapor pressure measurements indicate a normal boiling point of −32.6±0.9°C and an enthalpy of vaporization of 23.37±0.26 kJ/mol. The infrared spectrum of the vapor is consistent with the molecule being isostructural with CH 3 OH and CF 3 OF. The compound has also been characterized by mass spectrometry and by 1 H, 19 F, and 13 C NMR spectrometries. This novel reagent adds across various double bonds to form the corresponding fluoro methoxy adducts, which are not easily accessible by other methods

F 2 reacts with water and CH 3 CN, apparently to produce the relatively stable complex HOF•CH 3 CN. This is probably the best known oxygen-transfer reagent and can epoxidize olefins quickly and efficiently. Various types of alkenes including aliphatic, benzylic, enones, dienones, maleates, and fumarates have been examined, and all react with the reagent to produce the corresponding mono- or diepoxides in good to excellent yields. This epoxidation is fully stereospecific, and the configuration of the starting olefin is fully retained in the resulting oxirane.In cases where exceptionally stable oxocarbocations can be formed as in 1,1-diphenylethene, the reaction produces vicinal glycols in good yields. Since the origin of the epoxides' oxygen is in the water, this method is very suitable for introducing the isotopes 17 O and 18 O into various molecules

Fluorine reacts with wet acetonitrile to produce an oxidizing agent which oxidizes all types of aromatic amines to the corresponding nitroarenes, also offering a way to make 18O containing nitro derivatives.

The strong oxidant produced by the reaction of elemental fluorine with acetonitrile containing ca. 10% water has been shown to be hypofluorous acid, HOF, which is stabilized by complexing to the solvent. The reaction represents a new and convenient method of preparing and handling HOF, a unique oxygenating reagent. The presence of acetonitrile results in subtle but significant changes in the chemical behavior of the HOF. Vibrational and NMR spectroscopic studies of the solutions resulting from this reaction, as well as of solutions prepared by dissolving neat HOF in dry acetonitrile, have shown that the complex is a 1:1 hydrogen-bridged entity, in which the HOF proton is most likely bonded to the nitrogen atom of the nitrile. The 19 F NMR data indicate that the complexation reaction has an equilibrium constant of ca. 3 at room temperature, and that the enthalpy of formation of the complex is −14.3 ± 0.5 kJ mol −1 . The success of this method of synthesizing hypofluorous acid is a consequence of the very slow reaction between HOF and low concentrations of water in acetonitrile. This reaction accelerates drastically as the water content increases. As the solution composition approaches 100% water, the rate constant appears to approach a limit of about 0.7 s −1 at 25 °C, which may be the actual rate of reaction of HOF with the water.

The complex HOF·CH3CN, made directly from fluorine and aqueous acetonitrile, was used for oxidation of secondary alcohols and for Baeyer Villiger oxidation of ketones. By using 18O labeled reagent it was found that the ketone oxidation proceeds through the original dioxirane mechanism which Baeyer and Villiger suggested a century ago for reactions with peracids but was later discounted.

Methyl hypofluorite was until recently grouped as a hypothetical member of those smallest organic molecules which had not been synthesized. Passing F 2 through a solution of methanol in MeCN or PrCN resulted in its successful preparation. MeOF is an unique reagent, since it generates the novel electrophilic methoxylium moiety in contrast to the much more common methoxide group. This hypofluorite was reacted with several types of olefins including benzylic, cyclic, bicyclic, straight chain, and steroidal ones. In most cases the regioselectivity is very good, reflecting the unique polarization of the reagent: MeO δ+ F δ- . The stereoselectivity tends to be less emphasized, but usually anti addition is dominant

A selective synthesis of 2-amino-N-alkylbenzylamines by direct mono alkylation of 2-aminobenzylamine is achieved by a potassium tert-butoxide/alkyl halide treatment of a 9-BBN amine-aminoborane chelate.

A convenient route for the synthesis of a variety of salan-type compounds is introduced. The synthesis is based on a single-step Mannich condensation between readily available starting materials: primary or secondary amines, formaldehyde and substituted phenols. This methodology is suitable for the preparation of chiral salans as well, which may find applications in asymmetric catalysis.

[reaction: see text] A method for selective mono-N-alkylation of amino alcohols is introduced. This method relies on formation of a stable chelate with 9-BBN, which serves in the dual roles of protecting and activating the amine group. Three prototypical amino alcohols featuring various three-carbon bridging units led selectively to the monoalkylated derivatives in very high yields. The straightforward synthesis of the N-CD3 derivatives demonstrates the effectiveness of this approach.