Butane Synthesis

Polymer molecular properties. Making a polymer of high quality is much more complicated than making butanal, for example, because the material properties of a polymer depend heavily on a number of molecular properties. For example, 1% of mistakes in a propene polymer chain can spoil the properties of a polymer completely (crystallinity for instance), while 10% of a by-product in a butanal synthesis can be removed easily by distillation. PVC contains only 0.1% defects as allylic and tertiary chlorides and this necessitates the use of a large package of stabilisers ... 

TRANSITION METAL CATALYZED REACTIONS OF BICYCLO[ 1.1.0]BUTANES SYNTHESIS OF 1185 ALLYLCYCLOPROPANES... 

To illustrate how aldol condensation may be coupled to functional group modifi cation consider the synthesis of 2 ethyl 1 3 hexanediol a compound used as an insect repellent This 1 3 diol is prepared by reduction of the aldol addition product of butanal... 

Outline a synthesis of 2 ethyl 1 hexanol from butanal... 

Since 1960, the Hquid-phase oxidation of ethylene has been the process of choice for the manufacture of acetaldehyde. There is, however, stiU some commercial production by the partial oxidation of ethyl alcohol and hydration of acetylene. The economics of the various processes are strongly dependent on the prices of the feedstocks. Acetaldehyde is also formed as a coproduct in the high temperature oxidation of butane. A more recently developed rhodium catalyzed process produces acetaldehyde from synthesis gas as a coproduct with ethyl alcohol and acetic acid (83—94). 

Commercial production of acetic acid has been revolutionized in the decade 1978—1988. Butane—naphtha Hquid-phase catalytic oxidation has declined precipitously as methanol [67-56-1] or methyl acetate [79-20-9] carbonylation has become the technology of choice in the world market. By-product acetic acid recovery in other hydrocarbon oxidations, eg, in xylene oxidation to terephthaUc acid and propylene conversion to acryflc acid, has also grown. Production from synthesis gas is increasing and the development of alternative raw materials is under serious consideration following widespread dislocations in the cost of raw material (see Chemurgy). 

Currently, almost all acetic acid produced commercially comes from acetaldehyde oxidation, methanol or methyl acetate carbonylation, or light hydrocarbon Hquid-phase oxidation. Comparatively small amounts are generated by butane Hquid-phase oxidation, direct ethanol oxidation, and synthesis gas. Large amounts of acetic acid are recycled industrially in the production of cellulose acetate, poly(vinyl alcohol), and aspirin and in a broad array of other... 

Because of the large price differential between propane and propylene, which has ranged from 155/t to 355 /1 between 1987 and 1989, a propane-based process may have the economic potential to displace propylene ammoxidation technology eventually. Methane, ethane, and butane, which are also less expensive than propylene, and acetonitrile have been disclosed as starting materials for acrylonitrile synthesis in several catalytic process schemes (66,67). 

Historically, formaldehyde has been and continues to be manufactured from methanol. EoUowing World War II, however, as much as 20% of the formaldehyde produced in the United States was made by the vapor-phase, noncatalytic oxidation of propane and butanes (72). This nonselective oxidation process produces a broad spectmm of coproducts (73) which requites a complex cosdy separation system (74). Hence, the methanol process is preferred. The methanol raw material is normally produced from synthesis gas that is produced from methane. 

Production of maleic anhydride by oxidation of / -butane represents one of butane s largest markets. Butane and LPG are also used as feedstocks for ethylene production by thermal cracking. A relatively new use for butane of growing importance is isomerization to isobutane, followed by dehydrogenation to isobutylene for use in MTBE synthesis. Smaller chemical uses include production of acetic acid and by-products. Methyl ethyl ketone (MEK) is the principal by-product, though small amounts of formic, propionic, and butyric acid are also produced. / -Butane is also used as a solvent in Hquid—Hquid extraction of heavy oils in a deasphalting process. 

Prior to 1975, benzene was catalytically oxidized to produce maleic anhydride, an intermediate in synthesis of polyester resins, lubricant additives, and agricultural chemicals. By 1986 all commercial maleic anhydride was derived from oxidation of / -butane. It is expected that / -butane will remain the feedstock of choice for both economic and environmental reasons. 

This process may be competitive with butane oxidation (see Hydrocarbon oxidation) which produces a spectmm of products (138), but neither process is competitive with the process from synthesis gas practiced by Monsanto (139) and BASF (140) which have been used in 90% of the new acetic acid capacity added since 1975. 

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... 

Butan-3-one, 2-hydroxy-2-(indolyl)-photodecomposition, 4, 233 Butan-3-one, 2-hydroxy-2-(pyrrolyl)-photodecomposition, 4, 233 Butazolidines applications, 5, 782 Butazone, y-hydroxyphenyl-antiinflammatory agents, 5, 296 Butazone, phenyl-metabolism, 1, 239, 5, 301 synthesis, 5, 230 But-l-ene, 1-morpholino-polymers, 1, 291... 

The synthesis of 1-ethoxy-1-butjme has been reported previously, but the preparations have required multistep sequences. Two of the procedures use 1,2-dibromo-l-ethoxy butane which is dehydrohalogenated in two successive steps, first by an amine base and then by either powdered potassium hydroxide or sodium amide no yields are given. The... 

Craig s synthesis of nicotine (V to VII, p. 42) proceeds via nomicotine. Nicotinic acid nitrile reacts with the Grignard reagent derived from ethyl y-bromopropyl ether to give 3-pyridyl-y-ethoxypropyl ketone (V). This yields an oily oxime (VI) reducible to a-(3-pyridyl)-a-amino-8-ethoxy-w-butane (VII), which with 48 per cent, hydrobromic acid at 130-3° gives womicotine, and this on methylation yields dZ-nicotine. 

In the development of thiophene chemistry three periods can be clearly distinguished the Victor Meyer era, the Steinkopf period, and the modem development starting with the discovery of the synthesis of thiophene from butane and sulfur, making thiophene potentially available in unlimited amounts. Hartough in his well-known monograph, has reviewed the intense and hectic thiophene research toward the end of the 1940 s carried out mainly at the Socony-Vacuum laboratories, but also at many academic institutions. An article by Nord et al. appeared in 1955 in which the research work in thiophene chemistry at Fordham University, as well as progress in general up to 1954, was reviewed. 

Synthesis and chemistry of substituted l-azabicyclo[1.1.0]butanes 97SL1029. Synthesis of aziridines via stereoselective reactions with imines 99PAC1033. 

Finke, P. E., Oates, B., Mills, S. G., MacCoss, M., Malkowitz, L., Springer, M. S., Gould, S. L., DeMartino, J. A., Carella, A. Carver, G., et al. (2001). Antagonists of the human CCR5 receptor as anti-HIV-1 agents. Part 4 synthesis and structure—Activity relationships for l-[7V-(Methyl)-7V-(phenylsulfonyl)amino]-2-(phenyl)-4-(4-(7V-(alkyl)-7V-(benzylox-ycarbonyl)amino)piperidin-l-yl)butanes. Bioorg. Med. Chem. Lett. 11 2475-2479. 

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