Nitrogen trihalides

Propose an explanation for the fact that the nitrogen trihalides become less stable as the molar mass of the halo., increases. 

Noncombustible gas bums with fuels, hydrocarbons, or when heated with hydrogen. Nitric oxide reacts violently with carbon disulfide vapors, producing green luminous flame with fluorine, it produces a pale yellow flame. It explodes when mixed with ozone, chlorine monoxide, or a nitrogen trihalide. Reactions with many pyrophoric metals produce incandescence. Reaction with amorphous boron produces brilliant flashes. 

Ammonia reacts violently with halogens. At ordinary temperatures, a mixture of ammonia-fluorine bursts into flame. On heating, the products, nitrogen trihalides resulting from reactions with halogens, explode violently. Violent reactions occur with many interhalogen compounds of fluorine, as well as with many inorganic chlorine compounds. The latter include chlorites, hypochlorites, chlorine monoxide, and certain metal chlorides, such as silver chloride or mercuric chloride, which form shock-sensitive nitrides. 

In ammonia and the nitrogen trihalides, there is a non-bonding pair of electrons, leading to a pyramidal molecular shape. 

The complexes Fe(CNR)4(CN)2 (R = H, CH3, C2H5) are reported to form 1 2 complexes with boron trihalides (65). In these complexes the BX3 group coordinates to the cyanide nitrogen, giving the ligand group [CNBXj] . A mention of a similar complex was made earlier 161). 

The metal reacts with halogens above 200°C forming its trihalides. It combines with nitrogen above 1,000°C producing a nitride, YN. It combines at elevated temperatures forming binary compounds with most nonmetals and some metalloid elements such as hydrogen, sulfur, carbon, phosphorus, silicon, and selenium. 

A methyl ester was formed by methanolysis of a trihalide (Equation 32) <2007S225>. Decarboxylation of the /3-ketoacid resulting from hydrolysis has also been reported (Equation 33) <1980LA1917>. A carboxylic acid substituent was reduced to aldehyde with LAH (Equation 34) <1974J(P1)2092>. Thiazine nitrogen probably participates in this reaction. 

When looking for other molecules with lone electron-pairs that perhaps will combine these electrons with d electrons of platinum metals, there are, first of all, the trihalides of the nitrogen-phosphor group of elements. Complexes formed from chlorides of the platinum... 

BC13 has a hexagonal bimolecular cell, Cj , P63, with a = 6.08 and c = 6.55 A. The trigonal planar molecules are in A and B positions as for SbCls and Sb(CH3)3Br2 (Figures 4.26 and 4.27). All other boron halides are also planar. Phosphorus trihalides, like NH3 and nitrogen halides, are pyramidal because of the lone electron pair on P and N. 

Organo tellurium trihalides form complexes with coordinatively unsaturated metal halides and with ligands having nitrogen, oxygen, or sulfur donor atoms. 

Alkyl groups from alkyl aryl telluriums that have a stabilizing nitrogen functionality in the aromatic ring in an orr/zo-position to the tellurium atom are cleaved by bromine, iodine or sulfurylchloride. Aryl tellurium halides or trihalides are produced in these reactions. 

Boron trihalide adducts of 4-methylpyridine show halogen exchange behavior similar to that of the adducts of trimethylamine 10), and isolation of individual mixed-halogen species is feasible here too. The stability of nitrogen-donor adducts of the mixed boron trihalides parallels the stability of nitrogen-donor adducts of BH2X and BHX2 which have been more extensively studied 19, 153,156). 

A convenient apparatus for this transfer from the ampul is shown in Fig. 116. The frozen ampul, the neck of which is scored by a scratch mark, is attached to the frit arm by thick-walled rubber tubing, and the complete apparatus is evacuated. The scored portion of the neck extends inside the wider-bore frit arm. The apparatus is filled with nitrogen, and the ampul is allowed to warm until the methyltitanium trihalide has melted and dissolved in its oc-... 

Trihalides of nitrogen with fluorine and chlorine can be isolated, but with bromine and iodine only the ammonia complexes, NBr3(NHg)g and Nl3(NH3), are known. 

Direct gas sources provide an easy way of introducing impurities into a diffusion furnace, and they can be diluted by a carrier gas, (e.g., dopant trihalides or hydrides can be diluted with nitrogen mixed with oxygen). The vapor phase reactions produce on the semiconductor surfaces dopant oxides from which diffusion can occur. 

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