Amyl alcohols Production reactions

Di-n-amyl ether. Use 50 g. (61 5 ml.) of n-amyl alcohol (b.p. 136-137°) and 7 g. (4 ml.) of concentrated sulphuric acid. The calculated volume of water (5 ml.) is collected when the temperature inside the flask rises to 157° (after 90 minutes). Steam distil the reaction mixture, separate the upper layer of the distillate and dry it with anhydrous potassium carbonate. Distil from a 50 ml. Claisen flask and collect the fractions of boiling point (i) 145-175° (13 g.), (ii) 175-185° (8 g.) and (iii) 185-190° (largely 185-185-5°) (13 g.). Combine fractions (i) and (u), reflux for 1 hour in a small flask with 3 g. of sodium, and distil from the sodium amyloxide and excess of sodium this yields 9 5 g. of fairly pure n-amyl ether (iv). The total yield is therefore 22 - 5 g. A perfectly pure product, b.p. 184 185°, is obtained by further distillation from a Little sodium. 

Dehydration. Dehydration of amyl alcohols is important for the preparation of specialty olefins and where it may produce unwanted by-products under acidic reaction conditions. Olefin formation is especially facile with secondary or tertiary amyl alcohols under acidic conditions. The reverse reaction, hydration of olefins, is commonly used for the preparation of alcohols. 

Eriedel-Crafts alkylation of ben2ene with isomeric amyl alcohols proceeds with some rearrangement. Eor example, both 2- and 3-pentanol gave the identical product mixture (60% 2-phenylpentane, 31% 3-phenylpentane, and 9% / f/-pentylben2ene) from reaction with ben2ene in the presence of BE catalyst (85). 

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. 

Prior to 1975, reaction of mixed butenes with syn gas required high temperatures (160—180°C) and high pressures 20—40 MPa (3000—6000 psi), in the presence of a cobalt catalyst system, to produce / -valeraldehyde and 2-methylbutyraldehyde. Even after commercialization of the low pressure 0x0 process in 1975, a practical process was not available for amyl alcohols because of low hydroformylation rates of internal bonds of isomeric butenes (91,94). More recent developments in catalysts have made low pressure 0x0 process technology commercially viable for production of low cost / -valeraldehyde, 2-methylbutyraldehyde, and isovaleraldehyde, and the corresponding alcohols in pure form. The producers are Union Carbide Chemicals and Plastic Company Inc., BASF, Hoechst AG, and BP Chemicals. 

In the production of KNO3 from KCl and HNO3, the product HCl is removed continuously from the aqueous phase by contact with amyl alcohol, thus forcing the reaction to completion (Daniel and Bhimberg, Chim. Jnd., 4, 27 [1957]). 

The reaction conditions were optimized to afford clean coupling of enol tosylate 32 using only a slight excess of amide 24 (1.05equiv) at 100 °C, 5mol% Pd2(dba)3/ dppb catalyst, and a toluene/tert-amyl alcohol solvent system. Even under the harsh reaction conditions required for complete conversion of the tosylate (100 °C, 20 h) no detectable E/Z isomerization was seen, providing further proof that the hindered nature of the enamide aids stability to isomerization. Treatment of the mixture with activated carbon (Darco KB-B) at the end of the reaction followed by isolation of the product by crystallization, afforded enamide 22 in 92% isolated yield. 

CTABr or C16H33NMe2CH2CH2OH Br , t-amyl alcohol or 1-butanol, aq.NaOH. Overall reaction rates and products examined... 

A mixture of tetracyanodibenzo-[l,4,7,10-tatrathia-12-crown] (1) (0.050 g, 0.115 mmol), 4-nitrophthalonitrile (2) (0.150 g, 0.690 mmol) and zinc(ll) acetate (0.050 g, 0.230 mmol) was refluxed in amyl alcohol under argon for 6 h (Scheme 42.1). The reaction mixture was cooled down to room temperature and precipitated by adding methanol. After filtration, the product was washed with methanol, chloroform and acetone. This compound was soluble in tetrahydrofuran (THF), dimeth-ylformamide (DMF) and dimethylsulfoxide (DMSO). 

Diammino-uranyl Nitrate, [U02(NH3)2](N03)2, is formed when dry gaseous ammonia is passed into a boiling solution of dry uranyl nitrate in amyl alcohol until the liquid is decolorised. A voluminous yellow precipitate is formed, which is collected and dried in vacuo over sulphuric acid. The product is only freed from amyl alcohol by repeated evacuation over fresh quantities of sulphuric acid. It is a yellow amorphous powder, which is insoluble in ether and amyl alcohol. If the diammine is prepared in ether the same reaction takes place, and, after evacuation over sulphuric acid, a bright yellow powder is obtained of composition [UO2(NH3)2](NO3)2.C2H10O this, on keeping in vacuo, gradually loses ether, yielding the diammino-nitrate. 

The largest offtake of acetone is its conversion into solvents, used mainly in lacquers and other synthetic resin applications. These solvents include diacetone alcohol, methyl isobutyl ketone, methyl isobutyl carbinol (methyl amyl alcohol), and methyl amyl acetate. The following equations (22), in each of which the raw material is the product of the previous reaction, show a possible procedure by which these solvents may be made ... 

Friedel-Crafts alkylation of benzo[6]thiophene has received little attention. The published results, which deserve reexamination, indicate that exclusive 3-substitution occurs in some cases, whereas in others, 2-substitution predominates. Benzo[6]thiophene is alkylated with isopropyl chloride, isopropanol, or propene in the presence of various acid catalysts under a variety of reaction conditions to give a mixture of 2- and 3-isopropylbenzo[6]thiophene in which the 2-isomer predominates (78-92%).358 410 In contrast, alkylation with isobutene in the presence of either 80% sulfuric acid415 or 100% phosphoric acid416 is said to afford exclusively 3-/er<-butylbenzo[6]thiophene in yields of 100 and 75%, respectively. In neither case was the structure of the product rigorously confirmed. Likewise, 3-Jeri-amylbenzo [63-thiophene is the exclusive product of alkylation with tert-amyl alcohol in the presence of stannic chloride414 alkylation with pent-l-ene, hex-l-ene, and a Ci8 propylene polymer is also claimed to give... 

The carbonyl functionality of MIBK can be hydrogenated over nickel catalysts to yield methyl isobutyl carbinol (4-methyl-2-pentanol or methyl amyl alcohol) [108-11-2]. Industrial processes coproduce methyl isobutyl carbinol during the hydrogenation of mesityl oxide to MIBK. The product ratio of methyl isobutyl carbinol—MIBK during this reaction can be shifted toward methyl isobutyl carbinol by adopting a higher than normal pressure and H2 organic ratio (59). Methyl isobutyl carbinol is used as an ore flotation frother and to produce zinc dialkyl dithiophosphate lube oil additives. It is produced in the United States by Shell and Union Carbide ( 1.12/kg, October 1994). 

Many of these solvents, e.g., carbon disulphide, amyl alcohol, amyl acetate, ether, benzene, etc., may be easily identified—especially if unmixed with other solvents—by their odour, density, b.pt. and various reactions (see chapter on Chemical Products, Vol. I, and Tables XXXV and XXXVI, opposite.)... 

The remaining 30 percent of 1-butene is divided among several uses. About 10-15 percent of the 1-butene is polymerized in the presence of a Ziegler-type catalyst to produce polybutene-1 resin. The markets for this resin are pipe, specialty films, and polymer alloys. Approximately the same volume of 1-butene is reacted with synthesis gas in an oxo reaction to produce valeraldehydes. These C5 aldehydes are then hydrogenated to amyl alcohols or oxidized to valeric acid. Amyl alcohols are consumed in the production of lube oil additives and amyl acetate and in solvent uses. Valeric acid goes into lubricant base stocks and specialty chemicals. 

Enzyme assays were conducted in a 10 mL screw-neck glass test tube containing 100 fiL of lysate, 90 fiL of a 250 /ng/mL solution of 6-mercaptopurine in 0.01 M HC1, and 15 /uL of 250 mM sodium phosphate buffer (pH 9.2). Reactions were initiated by the addition of 32 fiL of a 3 1 mixture of 250 fiM S-adenosyl-L-methionine and 30 mM dithiothreitol. The final pH was 7.5. After a 1-hour incubation at 37°C, the reaction was stopped by the addition of 850 fjL of ice-cold 3.5 mM dithiothreitol and 50 fih of 1.5 M H2S04. The tubes were then heated at 100°C for 2 hours. To each tube, 500 fiL of 3.4 M NaOH was added, immediately followed by 8 mL of toluene-amyl alcohol-phenyl mercuric acetate. The tubes were shaken for 10 minutes and centrifuged. Then 6 mL of the toluene layer was transferred to a glass-stoppered conical test tube and 0.2 mL of 0.1 M HC1 added. After vortex-mixing and centrifuging, the toluene layer was discarded. Samples (50 fiL in 0.1 M HC1) were used for HPLC analysis. Product formation was linear for up to 120 minutes and 150 /u,L of lysate. 

The reaction was carried out in a three-necked flask equipped with a stirrer, a water segregator with a reflux condense and a thermometer. To the flask were added a certain amounts of -amyl alcohol, cinnamic acid and the catalyst, which was heated to boiling and refluxed until no water flowed off. The purified product was analyzed by means of IR. 

Amyl alcohols occur in eight isomeric forms and have the empirical formula CjHnOH. All are liquids at ambient conditions except 2,2-dimethylpropanol (neopentyl alcohol), which is a solid. Almost all amyl alcohols are manufactured in the United States by the hydroformylation of butylenes. Yeast fermentation processes for ethanol yield small amounts of 4-methyl-l-butanol (isoamyl alcohol) and 2-methyl-1-butanol (active amyl alcohol, scc-butyl-carbinol) as fusel oil. However, when the amino acids leucine and isoleucine are added to sugar fermentations by yeast, 87% and 80% yields of 4-methyl-l-butanol and 2-methyl-l-butanol, respectively, are obtained (Fieser and Fieser, 1950). These reactions are not suitable for commercial applications because of cost, but they do indicate the close structural relationship between these C5 amino acids and the C5 alcohols. The reactions occur under nitrogen-deficient conditions. If a nitrogen source is readily available, the production of the alcohols is lowered considerably. 

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