Alcohols, tert 3-methyl-3-pentanol

Odor data for the various amyl alcohols is limited. The lowest perceptible limit for 1-pentanol and / fZ-amyl alcohol are 10 and 0.04 ppm, respectively (135). tert-Axa[. alcohol has a threshold value of 2.3 ppm (and a 100% recognition level of 0.23 ppm) 3-methyl-1-butanol has an odor threshold of 7.0 ppm. The odor of 1-pentanol has been described as sweet and pleasant whereas that of 3-methyl-2-butanol is sour (135). 

All eight amyl alcohol isomers are available from fine chemical supply firms in the United States. Five of them, 1-pentanol, 2-pentanol, 2-methyl-1-butanol. 3-methyl-l-butanol, and 2-methyl-2-butanol (tert-amvl alcohols) are available in bulk in the United States in Europe all but neopentyl alcohol are produced. 

SYNS tert-AiMYL ALCOHOL (DOT) AMYLENE HYDRATE DIMETHYLETHYLCARBINOL 2-METHYL BUTANOL-2 2-METHYL-2-BUTANOL 3-METHYLBUTAN-3-OL tert-PENTANOL... 

The values of the enthalpy obtained do not depend on the model chosen for the dimer, as shown by Lussan (19) in a comprehensive summary of the possible theoretical treatments of the NMR data. Lussan demonstrates the form of the equilibrium constant calculation in the case of (1) monomer-dimer (open or cyclic), (2) monomer-cyclic trimer, and (3) monomer-higher acyclic multimers in the two cases of (3a) all K s equal and (3b) ki for monomer-dimer equilibrium unique, k s for higher multimers all equal. He then takes the experimental curves for a number of alcohols in carbon tetrachloride and achieves a reasonable fit to the data up to 0.6 mole fraction by using one or the other of the theoretical relationships. In some cases two sets of theoretical points are plotted on the same graph as the experimental data both are a good fit in the low concentration region, up to 0.1 mole fraction. Above this concentration one or the other of the theoretical curves is much closer to the experimental curve. Lussan implies that hypothesis 3b may be a more accurate fit to the data in the more concentrated solutions. Methanol, ethanol, 2-methyl-2-propanol (tert-butyl alcohol) and 2,2,4-trimethyl-3-pentanol follow the curve for equilibrium 3a, while 2,2,4,4-tetramethyl-3-pentanol fits the monomer-dimer data. Lussan points out that the behavior of the latter alcohol fits in with that of two similar heavily substituted tertiary alcohols which have been found by infrared methods to form only dimers. 

Figure 7 Colour plot of a GCxGC separation of reformulated gasoline [35]. Ol. methanol, 02. ethanol, 03. isoproyl alcohol, 04. tert-butanol, 05. n-propanol, 06. sec-butanol, 07. iso butanol, 08. tert-pentanol, 09. n-butanol, OlO. methyl tert-butyl ether. Oil. diisopropyl ether, 012. ethyl tert-butyl ether, 013. tcrt-amyl methyl ether, Nl. cyclo hexane, N2. methylcyclo hexane, IS. 1,2-dimethoxy ethane as internal standard.

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