Primary Amyl Alcohol

Primary amyl alcohol, a mixture of isomers all of which ore primary alcohols, is composed of approximately 60% pentanol-1 (CH3CH2CH2CH2CH2OH)  

35% 2-methyl butanol-1 (CH3CH2CH(CH3)CH20H) and 5% 3-methyl butanol-1 

Carbonyl, aa C5 aldehyde Coefficient of expansion at 20 C Color, Pt-Co Distillation at 760 mm Ibp Dp 

Heat of vaporization at 133 C Purity, as primary amyl alcohols Refractive index at 20 C, n0 Solubility in water at 20 C Solubility of water in, at 20 C Specific gravity at 20/20 C 

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Mixtures of isomeric amyl alcohols (1-pentanol and 2-methyl-1-butanol) are often preferred because the different degree of branching imparts a more desirable combination of properties they are also less expensive to produce commercially. One such mixture is a commercial product sold under the name Primary Amyl Alcohol by Union Carbide Chemicals and Plastics Company Inc. 

Commercial primary amyl alcohol is a mixture of 1-pentanol and 2-methyl-1-butanol, iu a ratio of ca 65 to 35 (available from Union Carbide Chemicals and Plastics Company Inc. iu other ratios upon request). Typical physical properties of this amyl alcohol mixture are Hsted iu Table 2 (17). 

Table 2. Physical Properties of Primary Amyl Alcohol, Mixed isomers ...

Other Reactions. Primary amyl alcohols can be halogenated to the corresponding chlorides by reaction with hydrogen chloride in hexamethylphosphoramide (87). Neopentyl chloride [753-89-9] is formed without contamination by rearrangement products. A convenient method for preparing / f/-amyl bromide and iodide involves reaction of / f/-amyl alcohol with hydrobromic or hydroiodic acid in the presence of Li or Ca haUde (88). The metal haUdes increase the yields (85 —95%) and product purity. 

Fusel Oils. The original source of amyl alcohols was from fusel oil which is a by-product of the ethyl alcohol fermentation industry. Refined amyl alcohol from this source, after chemical treatment and distillation, contains about 85% 3-methyl-1-butanol and about 15% 2-methyl-1-butanol, both primary amyl alcohols. Only minor quantities of amyl alcohol are suppHed from this source today. A German patent discloses a distillative separation process for recovering 3-methyl-1-butanol from fusel oil (93). 

Pentanol 2-Methyl- 1-butanol Primary amyl alcohol mixed isomers... 

Union Carbide Chemicals and Plastics Company Inc. is the only producer of C-5 oxo derived alcohols (148,150) in the United States. About 75% of the 30,000 t of valeraldehyde and 2-methylbutyraldehyde produced by the oxo process was converted to the isomeric mixture of primary amyl alcohols in 1988 (150). The primary amyl alcohol mixture was available in tank car quantities for 1.02/kg in 1991. The Dow Chemical Company appears to have stopped commercial production of / fZ-amyl alcohol (151). 

The principal component of primary amyl alcohol, 1-pentanol, although itself a good solvent, is useful for the preparation of specific chemicals such as pharmaceuticals and other synthetics (153,154). Production of primary amyl acetate and its esters for solvent appHcations has seen low growth since the 1970s because of the decline of nitroceUulose lacquers and the introduction of new solvent systems. 

Primary Amyl Alcohols. Primary amyl alcohols (qv) are manufactured by hydroformylation of mixed butenes, followed by dehydrogenation (114). Both 1-butene and 2-butene yield the same product though in slightly different ratios depending on the catalyst and conditions. Some catalyst and conditions produce the alcohols in a single step. By modifying the catalyst, typically a cobalt carbonyl, with phosphoms derivatives, such as tri( -butyl)phosphine, the linear alcohol can be the principal product from 1-butene. 

TABLE 2. PHYSICAL PROPERTIES OF PRIMARY AMYL ALCOHOL, MIXED ISOMERS... 

Isobutanol use in the manufacture of zinc dialkyl dithiophosphates (ZDDP), anti-wear lube oil additives, represented 13 percent of domestic consumption. Other alcohols used in this application include methylamyl alcohol, primary amyl,alcohol, n-butanol, 2-ethylhexanol and isooctanol. 

A mixture of mainly 3-methylbutan-l-ol (primary isoamyl alcohol) [(CH3)2CH CH2 CH20H] with some 2-methylbutan-1 -ol (primary amyl alcohol) [CH3 CH2 CUiCH ) CH2OH]. C5Hi20 = 88.15... 

This is a commercial mixture of various primary amyl alcohols, marketed by Sharpies Solvents Corporation. The mixture is more effective as a starch fractionating agent than any of the components alone. 

In order to effect complete dissolution of starch at temperatures below 100°, Bauer and Pacsu recommended the use either of dilute alkali or of dilute acid solutions. Accoixling to their so-called alkali process, defatted corn starch is dissolved in 0.5 to 1.0 N alkali at room temperature. Sufficient mineral acid is added to the resulting solution to bring its pH within the limits of 10-4. After saturation with (for example) Pentasol (a mixture of primary amyl alcohols), the system is heated for several minutes at a temperature between 60° and 100° on cooling, an amylose precipitate is obtained which can readily be separated in an ordinary, industrial centrifuge. Addition of excess methanol to the supernatant liquor causes precipitation of the amylopectin. Different kinds of starches can be fractionated by this method. Starch concentrations of up to 5% are claimed to give about a 24% yield of amylose (showing an iodine value of 16.0%) and a 76% yield of amylopectin (with a 0.9% iodine absorption). 

Experiments with deuterated optically active primary amyl alcohol, fluorenone, and sodium ethoxide, for example, showed a direct transfer of hydrogen from the hydroxyl carbon to the carbonyl carbon atom without intervention of the solvent.41 We should expect that, like all carbonyl additions, hydride addition reactions would be acid-catalyzed. Apparently, in aluminum isopropoxide and isopropyl alcohol the optimum acid strength of the solution has been reached. Some alkoxide ions... 

Active primary amyl alcohol 2428 AdekaCarpol MBF100 2192... 

C.HaaO Primary amylic alcohol. C.HxaO Secondary amylic alcohol. CaH.aO Tertiary amylic alcohol. 

Valerianic acids—C4HtCO,OH—102.—Corresponding to the four primary amylic alcohols, there are four possible amylic or valeri- anic acids, of which three, I., II., and IV., are known. 

Activated attapulgite. See Attapulgite Activated carbon. See Carbon, activated Activated charcoal. See Charcoal, activated Activator 1102. See Dibutylammonium oleate Active 2. See Cocamide DEA Active 18. See Oleamide DEA Active amyl alcohol. See 2-Methyl-1-butanol Active carbon. See Carbon, activated Active dicumyl peroxide. See Dicumyl peroxide Active primary amyl alcohol. See2-Methyl-1-butanol... 

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