Brom benzene

Ethyl Benzene from brom-benzene and ethyl bromide. 

The brom-benzene (60 gnis.) and ethyl bromide (50 gins.) are mixed in a 1-litre flask fitted with a reflux condenser, and double the volume of dry ether added. 

This is prepared in the same manner as tin tetra-phonyl, using 25 gms. of powdered lead-sodium (8 per cent, sodium) and tho same quantity of brom-benzene. The mixture should be boiled for fifteen hours and then extracted with benzene. Pale yellow needles in.p. 224°. Yield, about 18 gms. 

Magnesium phenyl bromide is prepared by dissolving brom-benzene (16 gms.) in ether (80 c.c.) and adding gradually magnesium ribbon (2 4 gms.). The solution when ready, is treated with beuzo-phenone (18 gms.) in ether (50 c.c.), and when the main reaction is over it is completed by boiling on the water-bath for half an hour. 

Bromoform splits off hydrobromic acid and some free bromine, and yields as chief product perbromethylene, also per-brom benzene (Joistl). Hexabromethane occurs only in traces this was to be expected on account of its easy decomposability into bromine and perbromethylene. Some carbon monoxide... 

Mono-chlor-benzene Di-brom-benzene Hydroxy benzene Amino benzene Methyl benzene... 

When a halogen substitution product of benzene, e.g. brom benzene, is treated with a methyl halide and metallic sodium, toluene is obtained. This proves that toluene is methyl benzene. 

Ethyl Benzene.—By the same synthesis another hydrocarbon has been made from mono-brom benzene and ethyl bromide which has the empirical formula CsHio, but which must be mono-ethylbenzene. 

Durene is the i-2-4-5-tetra-methyl benzene. It has a camphor-like odor and is found in coal tar. It can be made from one of the di-brom meta-xylenes, viz., the i-3-di-methyl 4-6-di-brom benzene by Fit-tig s qmthesis. 

It will be recalled that the formation of the di-brom benzene resulted in the para and ortho compounds and no meta whereas the di-nitro benzene formed is the meta only. meta-Di-nitro benzene is a solid crystalline substance of pale yellow color, the crystals being fine needles melting point 90°. The ortho and para di-nitro benzenes have been prepared by other reactions. 

Tri-phenyl amine is prepared by treating a boiling solution of sodium in di-phenyl amine with brom benzene. The acid influence of the phenyl radicals gives to di-phenyl amine the property of forming a sodium compound which then reacts with the brom benzene. 

The direct chlorination or bromination of aniline takes place more easily than that of benzene, the result being the symmetrical tri-chlor or tri-brom aniline, viz., i-amino 2-4-6-tri-chlor benzene, C6H2CI3-(NH2) and I-amino 2-4-6-tri-brom benzene, CeH2Br3(NH2). The mono-halogen anilines are prepared by reducing mono-chlor nitro benzenes, or by halogenating acetanilide and then hydrolyzing. 

Also mono-brom benzene and sodium yield benzoic acid with carbon dioxide. 

S nithesis from Phthalic Acid.—ortho-VhXha Q, acid yields a mono-brom derivative in which the bromine is ortho to one carboxyl and meta to the other, i.e., 1-2-dicarboxy 3-brom benzene. This being an ortho- hXhsX c acid yields an anhydride. This anhydride condenses... 

For the solubility of Mixtures of di Chlor Benzene and di Brom Benzene in aqueous Ethyl Alcohol solutions see Thiel. 

High resistance to 02 attack has been reported for many Nl(II) chelates (80, 128, 281). Some loss (3-10%) of (R=n-butyl) occurred In brom-benzene solution after exposure to I02 from a microwave discharge system (274). 

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