Iso Propyl alcohol

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. 

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

Jso-propyl alcohol is very difficult to dry satisfactorily. The water binary mixture, boiling at 80.35°, contains 12.1 per cent of water by weight. The ternary mixture with benzene, boiling at 66.5°, contains 73.8 per cent benzene, 18.7 per cent iso-propyl alcohol and 7.5 per cent water. Hence by adding 120 g. of dry benzene to 100 g. of the iso-propyl-water binary, and distilling off until the temperature reaches 82°, there will remain 55 to 60 g. of nearly dry iso-propyl alcohol. The commercial anhydrous alcohol was used in this preparation. 

Tne recovered benzene and excess iso-propyl alcohol may be dried by distillation and used in a subsequent run. 

Jso-propyl lactate has been prepared by heating iso-propyl alcohol and lactic acid in a sealed tube at 1700,1 2 and from silver lactate and iso-propyl iodide, together with the iso-propyl ester of a-iso-propoxy-propionic acid.3 Direct esterification of the acid with the alcohol, with sulfuric acid, has failed to give a yield greater than 20 per cent of the theoretical amount, and the product has been less pure. 

Unless otherwise stated, the reduction was carried out with aluminum isopropoxide in boiling iso propyl alcohol solution. C refers to clarified but undistilled aluminum isopropoxide D, to distilled reagent and U, to an untreated solution of the alkoxide (see p. 199). 

Propyl alcohol1 shows a somewhat greater resistance to oxidation. Propionic acid is the chief product, and a good yield is obtained at platinum or lead peroxide anodes in sulphuric acid. Iso-propyl alcohol which is more easily oxidised gives a 70 per cent, yield of acetone. 

The esterification step occurs with 85% sulfuric acid at 24 to 27°C, and dilution to 20% concentration is done in a separate tank. The iso-propyl alcohol is distilled from the dilute acid that is concentrated and returned to the esterification reactor. The /so-propyl alcohol is originally distilled as a 91% azeotrope with water. Absolute iso-propyl alcohol, boiling point 82.5°C, is obtained by distilling a tertiary azeotrope with isopropyl ether. A 95% yield is realized. 

Abate and abate residues Silical gel G Hexane acetone (10 1) Water extracted with chloroform Rf Abate 0.10-0.12 (red spot on yellow background Red spots with 10% N,N,dimethyl-p-phenylazo) aniline spray (Cl solvent yellow 2) in 95% iso propyl alcohol 9pg [89]... 

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