Mercuric Azide Additions

The electrophilic character of mercuric salts towards 7r-bonded carbon compounds is well known Nucleophilic attack on the 

The method has recently been adapted for azide synthesis by Sokolov and Reutov who reacted mercuric nitrate and sodium azide in dimethylformamide with alkenes such as styrene and cyclohexene The azidomercurials were isolated as the mercurichlorides in 10-25% yield. 

Heathcock independently reported an essentially similar procedure using mercuric azide generated from sodium azide and mercuric acetate in 50% aqueous tetrahydrofuran. The products were reduced in situ with sodium borohydride to afford alkyl azides (equation 93). These results are summarized in Table 7. 

Heathcock has observed that secondary and tertiary alkyl azides are obtained in good yields from terminal alkenes, but that non-terminal alkenes are relatively unreactive, except where reactivity is enhanced by steric strain as in norbornene. The order of reactivity in this reaction is similar to that in hydroxymercuration. A correlation between the reactivity sequence for azidomercuration and the known order of alkene-Ag stability constants was also apparent zmd Heathcock therefore proposed a mechanism which entails a rapid equilibrium involving the ion 197 which affords the organomercury 

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It becomes a problem in semantics to set a time limit for "development within which a process can be considered "spontaneous or "instantaneous . These two words seem to apply well to such extremely sensitive compounds as Nitrogen Triodide and Cupric Azide, which explode at the slightest touch when dry and, in addition, explode at a fairly low temperature. Attempts to correlate initiation in such cases with the attainment of a certain temperature seem unrealistic, especially in view of differences between relative sensitivity of different compounds to mechanical and thermal influences. For example, Mercuric Azide is so sensitive to impact that it explodes even under water, hut its heat sensitiveness is about the same as that for Cadmium Azide, which has been reported not to explode by percussion (Ref 5) Information about susceptibility of different explosives to spontaneous detonation is highly important from the viewpoint of safety. In Refs which follow are listed examples of spontaneous detonations of substances, some of them previously considered safe in this respect... 

OLEFIN ADDITIONS Benzenesulfonyl azide. Chlorosulfonyl isocyanate. Chiom-ous chloride. Cyanamlde. Dichloroketene. Dinitrogen tetroxide-Iodine. Diphenyl-ketene. Ethoxyketene. Fluoroxytrifluoro-methane. Iodine. Iodine azide. Iodine isocyanate. Iodobenzene dichloride. Mercuric azide. Nitrosyl chloride. Nitrosyl fluoride. Nitryl iodide. Potassium f-but-oxide-Bromoform (dibromocarbene). 

Brimacombe s group have used the addition of mercuric azide to the 3-C-methylene derivative (262) to prepared branched-chain amino-sugars [e.g. (263)] as outlined in Scheme 100. - The conversion of the branched-chain azide... 

Addition of mercuric azide to l,2 5,6-di-0-isopropylidene-3-C-methylene-a-D-r/6o-hexofuranose yielded, after reductive demercuration, the branched-chain azide (291), which could be transformed into the corresponding acetamido derivative (292). The conversion of (291) into the 3,6-acetylepimino derivative (293) established that it has the n-gluco configuration (see Vol. 9, p. 106). 

The ds-addition of mercuric azide to a series of substituted cyclopropenes has been reported by Galle and Hassner (Scheme 32). The resulting cis-2-azidocyclopropylmercuric azides may be converted into the corresponding... 

This following article was sent to Strike by Osmium and Feck (are they the same person ). It involves the direct addition of azide to a terminal alkene (you-know-who) by the in situ production of the reactant mercury (II) azide from mercuric acetate and sodium azide (please don t ask) [80]. 

There are several methods available for the electrophilic addition of hydrogen and nitrogen to alkenes, dienes and alkynes. While the direct electrophilic addition of amines to these substrates is not feasible, aminomercuration-demercuration affords a very useful indirect approach to such amines. The addition of amides to C—C multiple bonds can be effected directly through the Ritter reaction or by the less direct, but equally useful, amidomercuration-demercuration process using either nitriles or amides. Similarly, H—N3 addition to alkenes can be carried out directly or via mercuration to produce organic azides. 

Olefin additions Bromine azide. Bromine chloride. Bromine (chlorine) dipyridine nitrate. N-Bromoacetamine. N-Bromoacetamide-DMSO-Water. N-Bromoacetamide-Hydrogen fluoride. n-Butyllithium. Dichloroketene. Dichloromethyl 2-chloromethyl ether. N,N-Dichlorourethane. Dichlorovinylene carbonate. Difluoramine. Ethyl azidoformate. Ethyl bromoacetate. Iodine azide. Iodine isocyanate. Iodine nitrate, lodobenzene dichloride. 1-lodoheptafluoropropane. Mercuric acetate. Nitrosyl chloride. Nitrosyl fluoride. Nitryl iodide. Rhodium trichloride. Silver fluoride. 

The ferric color test for thiocyanates is not applicable in the presence of iodides because the iodine liberated by the redox reaction 2 Fe+ + 2 I -> 2 Fe+2 -f I2 makes it impossible to see the red ferric thiocyanate. The iodine-azide test may be carried out without modification if only small amounts of iodide are present. For reasons that are not yet clear, large amounts of iodide considerably reduce the sensitivity of the test. This interference can be obviated by the addition of mercuric chloride. The reaction Hg+2 + 4 1 [Hgl4] 2 produces complex mercuri-iodine anions which do... 

Since sulfides and thiosulfates likewise catalyse the iodine-azide reaction (pages 439, 453) such compounds must be removed. This is best carried out by the addition of mercuric chloride, which reacts with sulfides and thiosulfates ... 

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