Dichloride reactions with nitrogen

Li3(BN2) have already demonstrated the decomposition of (BN2) ions into boron nitride. The remaining nitride can lead to the formation of a binary metal nitride or reduce the transition metal ion under the formation of N2. Both mechanisms have been obtained experimentally, depending on the stability of the metal nitride. For instance niobium pentachloride forms NbN, titanium trichloride forms TiN, and nickel dichloride forms Ni, plus BN and nitrogen, respectively, in reactions with Li3(BN)2 (at 300-600°C) [24]. 

The quality of the refined metal, and the current efficiency strongly depend on the soluble vanadium in the bath and the quality of the anode feed. As the amount of vanadium in the anode decreases, the current efficiency and the purity of the refined product also decrease. A laboratory preparation of the metal with a purity of better than 99.5%, containing low levels of nitrogen (30-50 ppm) and of oxygen (400-1000 ppm) has been possible. The purity obtainable with potassium chloride-lithium chloride-vanadium dichloride and with sodium chloride-calcium chloride-vanadium dichloride mixtures is better than that obtainable with other molten salt mixtures. The major impurities are iron and chromium. Aluminum also gets dissolved in the melt due to chemical and electrochemical reactions but its concentrations in the electrolyte and in the final product have been found to be quite low. The average current efficiency of the process is about 70%, with a metal recovery of 80 to 85%. 

The conditions used for a radical reaction could require a modification of the mechanochemical polycondensation. Such a polycondensation of poly ( -caprolactam) was carried out using sebacic acid dichloride as a condensing agent. For the mechanochemical polycondensation of all the other polymers, aliphatic and aromatic diamines were used. In all cases, the reaction was followed by determining chemically linked nitrogen, which decreased in the first case (owing to the fixation of acid dichloride) and increased in the remaining ones because of the reactions with diamines. 

Undoubtedly, the most important stereochemical feature is chirality. The [2]-rotaxane depicted schematically in Figure 2.12a is made with a macrocycle and a dumbbell that are not themselves chiral but oriented by appropriate substitution patterns on these components. Vogtle and co-workers described cycloenantiomeric rotaxanes that are based on the amide templating functionality (Figure 2.13).36 Racemic [2]-rotaxane 34 was synthesized in 20% yield by reaction of unsymmetrical acid dichloride 32 with trityl aniline 33 in the presence of macrocycle 31. The object and its mirror image are created by different sequences of the amide and sulfonamide linkers in both the dumbbell and the macrocyclic component. If the order of the atoms within the dumbbell is examined, in one enantiomer the sulfonamide nitrogen atom is... 

The first phenolic derivative of ferrocene to be reported, di(l-hy-droxy-3-methyl-cyclopentadienyl) iron, was prepared by the reaction between 3-methyl-2-cyclopentanone, sodamide, and ferrous chloride in liquid ammonia. This compound is remarkably unstable, being extremely sensitive to air. It is a yellow substance which sublimes at 130-140° at 0.1 mm pressure, and is readily soluble in methylene dichloride but insoluble in carbon tetrachloride and in n-heptane. In water saturated with nitrogen a yellow solution is produced which rapidly bec( nes blue-green on exposure to air. The compound forms a benzoate (mp 121-123.5°) which is stable in air. An analogous derivative of the dicyclo-pentadienyl cobalt (III) cation has also been obtained (6). 

When the hydroxy group of amino alcohol was ccmverted into alkoxide, alkylation took place at the oxyanion in preference to the nitrogen atom. Thus, the sodium alkoxide derivative of (28) reacted with polyethylene glycol ditosylate or dichloride (29a-29c) to give the corresponding aminomethyl crown ethers (30). " Chiral amino alcohols (31) can be converted into amino ethers (32) via alkoxides. In contrast, treatment of iV-tosylamino alcohol (33) with NaH, followed by reaction with a fivefold excess of 1,2-dibromoethane afforded (34 Scheme 16).2 ... 

In the second step the reaction is less efficient because of quenching of the excited state of the diphenylamine component by the adjacent carbazole. Other cyclisations such as the conversion of (41) into (42) by irradiation in acetic acid have also been reported. As mentioned earlier cw-azobenzene derivatives cyclise under conditions where the nitrogens are protonated or complexed. A series of heavily substituted azobenzenes has been shown to undergo photochemical cyclodehydrogenation on irradiation in methylene dichloride solution with added SnCU- The reaction has been shown to be an efficient path to the heavily methylated cinnolines in good yield. 

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