Propyl alcohols

A number of physical and chemical properties of 1-propanol are Hsted ia Table 1 (2,3). The chemistry of 1-propanol is typical of low molecular weight primary alcohols (see Alcohols, higher aliphatic). Biologically, 1-propanol is easily degraded by activated sludge and is the easiest alcohol to degrade (4). 

1-Propanol has been manufactured by hydroformylation of ethylene (qv) (see Oxo process) followed by hydrogenation of propionaldehyde or propanal and as a by-product of vapor-phase oxidation of propane (see Hydrocarbon oxidation). Celanese operated the only commercial vapor-phase oxidation faciUty at Bishop, Texas. Since this faciUty was shut down ia 1973 (5,6), hydroformylation or 0x0 technology has been the principal process for commercial manufacture of 1-propanol ia the United States and Europe. Sasol ia South Africa makes 1-propanol by Fischer-Tropsch chemistry (7). Some attempts have been made to hydrate propylene ia an anti-Markovnikoff fashion to produce 1-propanol (8—10). However, these attempts have not been commercially successful. 

Hydroformylation and Hydrogenation. The production of 1-propanol by hydroformylation or 0x0 technology is a two-step process ia which ethylene is first hydroformylated to produce propanal. The resulting propanal is hydrogenated to 1-propanol (eqs. 1 and 2). 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

Propane, 1-propanol, and heavy ends (the last are made by aldol condensation) are minor by-products of the hydroformylation step. A number of transition-metal carbonyls (qv), eg, Co, Fe, Ni, Rh, and Ir, have been used to cataly2e the oxo reaction, but cobalt and rhodium are the only economically practical choices. In the United States, Texas Eastman, Union Carbide, and Hoechst Celanese make 1-propanol by oxo technology (11). Texas Eastman, which had used conventional cobalt oxo technology with an HCo(CO)4 catalyst, switched to a phosphine-modified Rh catalyst ia 1989 (11) (see Oxo process). In Europe, 1-propanol is made by Hoechst AG and BASE AG (12). 

Acidity as acetic acid Alkalinity as ammonia Autoignition temperature Boiling point at 760 mm 

APHA Critical density Critical pressure Critical temperature Distillation range at 760 mm 

Melting point Molecular weight Non-volatile material 

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Glycerol ct-dichlorohydrin, sym-dichloroiso-propyl alcohol, 1,3-dichloro-2-hydroxypropane, CH2CI-CHOH-CH2C1. Colourless liquid with an ethereal odour b.p. 174-175" C. Prepared by passing dry HCl into glycerin containing 2% elhanoic acid at 100-1 lO C. Converted to x-epichlorohydrin by K.OH, Used as a solvent for cellulose nitrate and resins. 

The student will doubtless be aware of the fact that methyl, ethyl, n-propyl and iso propyl alcohols are completely miscible with water. The solubilities of the higher aloohols decrease progressively as the carbon content increases. The solubilities of all types of alcohols with five carbon atoms or more are quite small. For the isomeric butyl alcohols the solubilities (g. per 100 g. of water at 20°) are n-butyl, 8 iso-butyl, 23 scc.-butyl, 13 ierl.-butyl, completely miscible. 

Carry out the Lucas test with iso-propyl alcohol, n-butyl alcohol, scc.-butyl alcohol, cycZohexanol and iert.-butyl alcohol. Obtain an unknown alcohol from the instructor for test. 

Propionaldehyde. Use 34 g. (42-6 ml.) of n propyl alcohol, and a solution containing 56 g. of sodium chromate dihydrate, 300 ml. of water and 40 ml. of concentrated sulphuric acid. The experimental details are identical with those for n-butyraldehyde, except that the addition of the dichromate solution occupies 20 minutes, the temperature at the top of the column is not allowed to rise above 70-75°, and during the subsequent heating for 15 minutes the liquid passing over below 80° is collected the receiver must be cooled in ice. The yield of propionaldehyde, b.p. 47-50°, is 12 g. 

Lactic acid iso-Propyl alcohol tso-Propyl lactate... 

Place a mixture of 25 5 g. of n-valerio acid (Sections 111,83 and 111,84), 30 g. (37 -5 ml.) of dry n-propyl alcohol, 50 ml. of sodium-dried benzene and 10 g. (5-5 ml.) of concentrated sulphuric acid in a 250 ml. round-bottomed flask equipped with a vertical condenser, and reflux for 36 hours. Pour into 250 ml. of water and separate the upper layer. Extract the aqueous layer with ether, and add the extract to the benzene solution. Wash the combined extracts with saturated sodium bicarbonate solution until effervescence ceases, then with water, and dry with anhydrous magnesium sulphate. Remove the low boiling point solvents by distillation (use the apparatus of Fig. II, 13,4 but with a Claisen flask replacing the distilling flask) the temperature will rise abruptly and the fi-propyl n-valerate will pass over at 163-164°. The yield is 28 g. 

If desired, the alcohol may be identified as the 3 5-dinitrobenzoate (Section 111,27) it is then best to repeat the experiment on a larger scale and to replace the dilute hydrochloric acid by dilute sulphuric acid. It must, however, be pointed out that the reaction is not always so simple as indicated in the above equation. Olefine formation and rearrangement of the alcohol sometimes occur thus n-prop3 lamine yields n-propyl alcohol, isopropyl alcohol and propylene. 

Esters of the homologous acids are prepared by adding silver oxide in portions rather than in one lot to a hot solution or suspension of the diazo ketone in an anhydrous alcohol (methyl, ethyl or n-propyl alcohol) methanol is generally used and the silver oxide is reduced to metallic silver, which usually deposits as a mirror on the sides of the flask. The production of the ester may frequently be carried out in a homogeneous medium by treating a solution of the diazo ketone in the alcohol with a solution of silver benzoate in triethylamlne. 

What happens during hydrolysis is that the OH forms and the elemicin propyl alcohol drops out of solution and forms its own oil layer. Of course one won t see this because the solution is a big old brown mess, lousy with emulsion particles. Emulsions suck But can be dealt with effectively by adding a little acid or base, or filtration and the like. Anyway, after a little work up one gets some really pure phenylpropyl compound. And if Strike had Strike s way. Strike would have that OH stuck right on the middle (beta) carbon of the species. Work could then progress on using that OH to get an amphetamine (Sob Strike had so much about that subject that Strike was prepared to put in this book ). 

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