Organic chemistry / by Frank C. Whitmore.

  • Frank C. Whitmore
Date:
1937
Catalogue details

Licence: In copyright

Credit: Organic chemistry / by Frank C. Whitmore. Source: Wellcome Collection.

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    presence of AlBr3 and CU2CI2 gives, among other products, 2,2- dimethylbutanol. Isopentane in vapor phase oxidation gives isovaleraldehyde, then isobutyraldehyde and finally acetone at which point the oxidation becomes slower (Edgar 1929). Iso- pentane with dil. nitric acid gives 2-nitro-2-Me-butane. With more concentrated acid it gives di- and trinitro compounds (EP 1042). The chlorination of mixed n- and fso-pentane has been devel- oped commercially (Ayres 1929, Clark 1930, EP 721, 726). A mixture of chlorine with a large excess of hydrocarbon is passed very rapidly through iron tubes at about 300°. The chlorine reacts completely with the formation of all the theoretically possible monochlorides and smaller amounts of higher chlorides. These chlorides are used as such or are converted to alcohols, olefins and acetates (Pentasol, Pentacetate, Sharpies). Pentane is used in thermometers for low temperatures. Neopentane (the prefix neo- indicates the presence of a C at- tached by all four valences to other C atoms), tetramethyl methane, (CH3)4C, b. 9.5°, is obtained by the action of dimethyl- zinc on acetone dichloride, 2,2-dichloropropane, prepared from acetone, and phosphorus pentachloride, or on a tertiary butyl halide. The best preparation is from ier-butyl chloride and methylmagnesium chloride (Whitmore 1933). Neopentane, on pyrolysis, gives methane and isobutylene (Frey 1933). On chlorination it gives neopentyl chloride, (CH3)3CCH2C1, without any rearrangement (Whitmore 1933). This chloride cannot be made from the corresponding alcohol (pp. 73, 128). The normal hydrocarbons from C5 to C12 have been obtained in high purity from suitable petroleum fractions by distillation, exhaustive treatment with chlorosulfonic acid (C1S03H) to remove all more active material and final careful distillation (Shepard, Henne, Midgley 1931). The following physical constants have been determined for the pure hydrocarbons: boiling point, melting point, density, (d420 and d425), index of refraction (n) at 20°, 25° and 45.3° for the a, D, and /3 lines, molecular refraction and dispersion, critical solution
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