Butanol synthesis from

As acetone is the least attractive product in the ABE fermentation, many efforts have been made to engineer the bacterial cells to produce butanol with minimal or no acetone. This goal has been achieved both in C. acetobutylicum natively and in many foreign hosts. However, all these successful cases rely on the direct n-butanol synthesis from acetyl-CoA, a process that will be discussed later in this chapter, and not via the native acid reassimilation. 

Butane, 2,3-0-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)-catalyst in homogeneous asymmetric hydrogenation, 6, 781 Butane-1,4-dioic acid, 2,2-di(indolyl)-synthesis, 4, 226 Butanenitrile, 4-hydroxy-dihydropyran synthesis from, 3, 769 Butanoic acid, -y-aryl-y-amino-synthesis, 1, 433 1-Butanol... 

Numerous nickel(II) complexes with a variety of polydentate amines have been described. Selected examples of such complexes are collected in Table 42. In general, solid complexes have been easily obtained by direct synthesis from nickel salts and the appropriate ligand using H20, MeOH, EtOH or butanol as reaction medium. Most of the complexes with the fully TV-alkyl-substituted ligands are conveniently prepared under anhydrous conditions. 

Olefin synthesis from a,p-unsaturated ketones. Ireland and Pflster1 have extended the procedure of Kenner and Williams (1,248, ref. 2) for deoxygenation of phenols to conversion of a,/3-unsaturated ketones into olefins. For example, the a,)3-unsaturated ketone (1) was reduced by lithium-ammonia to give an enolate anion which reacted with diethyl phosphorochloridate to give the phosphate ester (2) in 56% yield. This ester was reduced in high yield by lithium in a mixture of ethylamine and r-butanol to the olefin (3). It is noteworthy that only one olefin is formed. Actually the conversion of (1) into (3) can be carried out in 50% yield without isolation of the diethyl enol phosphate. 

By a similar mechanism to that proposed for the formation of ethyl ether by dehydration of ethanol, it is possible that the reaction occurs stepwise with the intermediate dehydration of one ethanol molecule to form ethylene which then reacts with another ethanol molecule to form butanol. It is thus possible that higher alcohols may be built up by the reaction of olefins with the lower alcohols. Mixed oxide type of catalysts are used in the process of a nature similar to those which have been found effective in alcohol synthesis from hydrogen and carbon monoxide. It should lie noted here that catalysts which promote the union of carbon atoms must be used, and since potassium oxide promoted catalysts composed of mixtures of zinc, copper, or chromium oxides have been found to be effective in the syuthesis of higher alcohols, such catalysts should be useful in promoting the addition of olefins to alcohols or other oxygenated organic molecules.77... 

Acetone dibutyl acetal has been prepared from isopropenyl acetate and butanol,2 from butanol and isopropenyl butyl ether obtained from the reaction of butanol with propyne,3 and by orthoformic ester synthesis.4-5... 

MTBE synthesis from /-butanol and methanol in a membrane reactor has been reported by Salomon et al. [2.453]. Hydrophilic zeolite membranes (mordenite or NaA) were employed to selectively remove water from the reaction atmosphere during the gas-phase synthesis of MTBE. This reaction was carried out over a bed of Amberlyst 15 catalyst packed in the inside of a zeolite tubular membrane. Prior to reaction, the zeolite membranes were characterized by measuring their performance in the separation of the equilibrium mixture containing water, methanol, /-butanol, MTBE, and isobutene. The results obtained with zeolite membrane reactors were compared with those of a fixed-bed reactor (FBR) under the same operating conditions. MTBE yields obtained with the PBMR at 334 K reached 67.6 %, under conditions, where the equilibrium value without product removal (FBR) would be 60.9%. 

The first asymmetric synthesis to achieve >90% optical yield was Brown s hydroboration of cis alkenes with diisopinocampheylborane (IpC2BH, Figure 7.10) in 1961 [130,131], The reagent was prepared by hydroboration of a-pinene of 90% ee 2-butanol obtained from hydroboration/oxidation of cw-2-butene had an optical purity of 87%, indicating an optical yield of 90%. ci5-3-Hexene was hydroborated in -100% optical yield. Since then, simple methods for the enantiomer enrichment of lpc2BH (and IpcBH2) have been developed [132-134], and enantioselectivities have been evaluated more carefully with the purified material. For example, lpc2BH of 99% ee affords 2-butanol (from cw-2-butene) in 98% ee and 3-hexanol (from ci5-3-hexene) in 93% ee, both determined by rotation (see Table 7.6, entries 1 and 5) [132]. ... 

Even while he was busy with the manufacture of ethylene oxide, Walter Reppe was also involved with the development of Buna synthetic rubber. In 1926, the newly formed I.G. Farben decided to embark on the industrial synthesis of rubber, despite the poor quality of the methyl rubber made during World War I. This time, however, it was agreed that butadiene would be used. Several routes to butadiene were investigated, including decyclization of cyclohexene (a retro-Diels-Alder reaction), but the so-called four-step process (Vierstufen Verfahren) soon won out. This was partly because it used acetylene, and hence surplus carbide from cyanamide manufacture, but also because it drew on the steps - and hence the momentum - of the BASF butanol synthesis. As a member of the former butanol group, Reppe was a natural candidate for the four-step process project. 

Synthesis gas, a mixture of mainly CO, CO2, and H2, has been used in chemical industry as feedstock and can be generated by gasification of coal and oil but also from biomass, municipal waste, or by recycling of used plastics (Kopke et al., 2010). Isobutanol production from synthesis gas has so far not been reported. However, Kopke et al. (2010) engineered Clostridium ljungdahlii, which is naturally able to use synthesis gas as carbon and energy source, for the production of 1-butanol by implementation of the CoA-dependent 1-butanol synthesis pathway from Clostridium acetobutylicum. The final titer of about 0.5 mM 1-butanol was rather low however, this approach demonstrated the feasibility to produce fuels and chemicals from synthesis gas. 

Following his accidental discovery of dibenzo-18-crown-6, Pedersen optimized its synthesis from catechol and diethylene glycol dichloride in n-butanol. A solution of... 

TiCl4 in oxygen [11], hydrolysis of titanium alkoxides in different conditions [12], photo-assisted sol-gel method from titanium tetrabutoxide [13], hydrothermal oxidation of metallic titanium powder [14], hydrothermal hydrolysis of titanium tetraethoxide [15], oxysulfate [16,17] and tetrabutylammonium [18], solvothermal synthesis from titanium butoxide in 2-butanol [19], crystallization of amorphous Ti02 in hydrothermal condition [20], vapor hydrolysis of titanium tetraisopropox-ide [21], destabilization of titanium lactate [22], decomposition of titania-hydrate [23], epoxide sol-gel process to aerogel of Ti02 [24], hydrolysis of aqueous solution of TiCl4 in the presence of polyethyleneglycol [25], and so forth. 

The selection of the catalyst system will often be determined by the process technique used. In the catalytic processing of acrylic acid-n-butyl ester synthesis from acetylene, carbon monoxide and n-butanol with nickel halogenide, troublefree continuous operation could not be achieved. 

Actual operating capacities of Reppe carbonylation processes are difficult to estimate since only a few data are available in the literature. However, it is known that some of the syntheses are carried out on an industrial scale, e. g. the synthesis of acrylates from acetylene, carbon monoxide and alcohols (BASF) [1004, 1005], the acetic acid synthesis from methanol and carbon monoxide and the synthesis of higher molecular weight saturated carboxylic acids from olefins, carbon monoxide and water. Propionic acid (30,000 tons/year) and to a smaller extent heptadecanoic dicarboxylic acid are manufactured via the carbonylation route at BASF. Butanol is made from propylene in Japan [1003, 1004]. 

The same products have been obtained by another route [447], The acyloin condensation of methyl /3-(m-methoxyphenyl)propionate (546) gives in poor yield t e acyloin (543), cyclization of which with polyphosphoric acid leads to a derivative of tetrahydrochrysene (544). Reduction of the central double bond of this compound both with sodium in liquid ammonia and with sodium in butanol takes place nonselectively leading to the dihydro derivatives (540) and (541) in a ratio of 2.1 1 in the first case and 1.25 1 in the second case. The further reduction of the trans isomer (540) by Birches method leads to the most thermodynamically stable trans-anti-trans-isomer (539) [447], the t -enantiomer of which has been obtained by partial synthesis from estradiol [222]. 

An example of a specialty olefin from an amyl alcohol is Phillips Petroleum s new process for 3-methyl-1-butene (used in the synthesis of pyrethroids) from the catalytic dehydration of 3-methyl-1-butanol (21,22). The process affords 94% product selectivity and 94% alcohol conversion at 310°C and 276 kPa (40 psig). 

Furalazine, Acetylfuratrizine, Panfuran-S. Heating nitrovin in butanol or dimethylformamide at 100—130°C affords furalazine, 6-[2-(5-nitro-2-furanyl)ethenyl]-l,2,4-triazine-3-amine (34). An improved synthesis originates with 5-nitro-2-furancarboxaldehyde and acetone, proceeds through 4-(5-nitro-2-furanyl)-3-buten-2-one followed by a selenium dioxide oxidation to the pymvaldehyde hydrate, and subsequent reaction with aininoguariidine (35). Furalazine, acetylfuratrizine (36), and the A[-A/-bis(hydroxymethyl) derivative, Panfuran-S, formed from the parent compound and formaldehyde (37), are systemic antibacterial agents. 

The second major discovery regarding the use of MTO as an epoxidation catalyst came in 1996, when Sharpless and coworkers reported on the use of substoichio-metric amounts of pyridine as a co-catalyst in the system [103]. A change of solvent from tert-butanol to dichloromethane and the introduction of 12 mol% of pyridine even allowed the synthesis of very sensitive epoxides with aqueous hydrogen peroxide as the terminal oxidant. A significant rate acceleration was also observed for the epoxidation reaction performed in the presence of pyridine. This discovery was the first example of an efficient MTO-based system for epoxidation under neutral to basic conditions. Under these conditions the detrimental acid-induced decomposition of the epoxide is effectively avoided. With this novel system, a variety of... 

The aqueous layer remaining after extraction with n-butanol was acidified (to pH 1) by the addition of 50% sulfuric acid, giving a precipitate of adipic acid which was collected by filtration, washed with 120 parts of water in two equal portions, and dried at 110° C. The crude adipic acid obtained was recrystallized from twice its weight of water to provide adipic acid in 90.2% yield, which was pure enough to be used in the synthesis of adiponitrile. 

Hydroformylation is an important industrial process carried out using rhodium phosphine or cobalt carbonyl catalysts. The major industrial process using the rhodium catalyst is hydroformylation of propene with synthesis gas (potentially obtainable from a renewable resource, see Chapter 6). The product, butyraldehyde, is formed as a mixture of n- and iso- isomers the n-isomer is the most desired product, being used for conversion to butanol via hydrogenation) and 2-ethylhexanol via aldol condensation and hydrogenation). Butanol is a valuable solvent in many surface coating formulations whilst 2-ethylhexanol is widely used in the production of phthalate plasticizers. 

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