I-Butanoic acid

During the attempted preparation of 3-p-chloropheny I butanoic acid by addition of the ketone (2 g mol) to peracetic acid (50%) in acetic acid at 65—70°C, a serious explosion occurred. 

In the mid to late 1980s, many research groups focused on methods and processes to prepare L-phenylalanine (Chapter 3). This was a direct result of the demand for the synthetic, artificial sweetener aspartame. One of the many routes studied was the use of phenylalanine dH (Scheme 19.4, R = C6H5CH2) with phenylpyruvate (PPA) as substrate.57-58 This enzyme from Bacillus sphaericus shows a broad substrate specificity and, thus, has been used to prepare a number of derivatives of L-phenylalanine.59 A phenylalanine dH isolated from a Rhodococcus strain M4 has been used to make L-homophenylalanine (.S )-2-amino-4-pheny I butanoic acid], a key, chiral component in many angiotensin-converting enzyme (ACE) inhibitors.40 More recently, that same phenylalanine dH has been used to synthesize a number of other unnatural amino acids (UAAs) that do not contain an aromatic sidechain.43... 

CjHhO.i, Butanoic acid, 3-oxo-, methyl ester, rhodium complex, 27 292 QH,N, Propane, 2-isocyant-2-melhyl-, ruthenium complex, 26 275 C,H,P, Phosphine, (2,2-dimethylpropyli-dyne)-, 27 249, 251... 

I) butanoic acid (II) heptanoic acid ( I) butane-1.4-dioic acid. 

Fig. 13. Chiral dendrimers of 2nd generation from trimesic and (i )-3-hydroxy-butanoic acid [56,57]...

Ruminant milk fats contain a high level of butanoic add (C4 0) and other short-chain fatty acids. The method of expressing the results in Table 3.6 (%, w/w) under-represents the proportion of short-chain adds-if expressed as mol %, butanoic acid represents c. 10% of all fatty acids (up to 15% in some samples), i.e. there could be a butyrate residue in c. 30% of all triglyceride molecules. The high concentration of butyric (butanoic) acid in ruminant milk fats arises from the direct incorporation of jS-hydroxybutyrate (which is produced by micro-organisms in the rumen from carbohydrate and transported via the blood to the mammary gland where it is reduced to butanoic acid). Non-ruminant milk fats contain no butanoic or other short-chain adds the low concentrations of butyrate in milk fats of some monkeys and the brown bear require confirmation. 

Butanoic Acid O-Nitroso-3.4-dichloro-penlafluoro- F,l6c, 19 (R COOilg I-NOCI)... 

C aH CVS,) see Temocillin (i)-3-(2-thlcnylthio)butanoic acid (ChIIiqOjSj 133359-80-5) see Dorzolainide 3-(2-thlenylthio)butanoic acid (CltH I102S2 120279-20-1) see Dorzolamide... 

These have the general formula of C H2 + i-CO OH. All the names of the acids end in oic and the series starts with n = 0 (Figure 4.7). The lower acids have the familiar smell of vinegar, but butanoic acid (n = 3) smells of rancid sweat. 

Propa, Propanoic acid Buta, butanoic acid Penta, pentanoic acid Hexa, hexanoic acid Hepta, heptanoic acid Octa, octanoic acid Nona, nonanoic acid Deca, decanoic acid Pal, palmitic acid St, stearic acid Piva, trimethylacetic acid Vers, Versatic acid a-BrHexa, a-bromohexanoic acid x-BrSt, a-bromostearic acid Me2(OH)Hexa, 2,5-dimethyl-2-hydroxyhexanoic acid a,a -DAC, a,a -dialkylcarboxylic acid Naph, naphthenic acid cy-PA, cyclopentylacetic acid cy-Hexa, cyclohexanecarhoxylic acid C7-C mix, C7-C9 mixture CB, chlorobenzene cy-Hexn, cyclohexane 1,2-DCE, 1,2-dichloro-ethane (i-Pr)2CO, diisopropyl ketone i-amOAc, isoamyl acetate i-amOH, isoamyl alcohol MIBK, 4-methyl-2-pentanone NB, nitrobenzene n-Hexn, n-hexane PE, petroleum ether TCB, 1,2,4-trichlorobenzene. 

I IS. Consider the compounds butanoic acid, pentanal, n-hexane, and 1-pentanol. The boiling points of these compounds (in no specific order) are 69°C, 103°C, 137°C, and 1 64°C. Match the boiling points to the correct compound. 

Nitrosohydr oxy lam i no)-1-butanoic Acid or a-Isonitraminobutyric Acid, (a-[Nitrosohydroxyl-amino]-but ter saure or a-lsonitraminobutters aure in Ger). HO.N(NO).CH(C2Hs).COOH, mw 148.12, N 18.91%. It is stable only in solns. May be prepd by passing NO gas through an ale soln of ethylic ethyl-acetoacetate to which some potassium ethylate was added, followed by saponification. Evaporation of this soln yielded a gummy substance which could not be crystallized (Refs 1 2)... 

Since 1 mol of acetic acid or butanoic acid reacts with I mol of benzyl bromide to produce 1 mol of benzyl acetate or benzyl butanoate, respectively, the O-acetyl content of the sample is calculated as follows ... 

By using aroma extract dilution analysis (AEDA) of the volatile fractions of fresh and stored butter oil, Widder et al. (29) determined diacetyl, butanoic acid, 8-octalactone, skatole, 8-decalactone, cw-6-dodeceno-8-decalactone, l-octen-3-one, and l-hexen-3-one as potent contributors to the flavor of butter oil. The concentration of l-octen-3-one, trani-2-nonenal, and i-l,5-octadien-3-one increased during the storage of the butter oil at room temperature. 

Reaction of l-chloro-4,4-bis(chloromethyl)pentane with magnesium in diethyl ether, followed by quenching with carbon dioxide, gave 4-(l-methylcyclopropyl)butanoic acid in 68% yield. Cyclopropane derivatives with electron-withdrawing substituents 5 were prepared by elec-troreductive dechlorination of 2,4-dichlorobutanoic acid derivatives in dimethyl sulfoxide solution in the presence of tetraethylammonium 4-toluenesulfonate at ambient temperature (yields 51 -90%).The starting materials for compounds 5 can easily be obtained by copper (I)-catalyzed photochemical addition of dichloromethane to electron-deficient alkenes. Electrochemical reductive 1,3-debromination has also been achieved however, it is of little synthetic value (experimental details are described in ref 16, with yields ranging from 39 to 94%). meso- and dimethyl sulfoxide gave equal amounts of cis- and transA, 2-dimethylpropane. ... 

A solution of 0.7 g (7 mmol) of triethylamine in 10 mL of chloroform was added to a solution of 7 mmol of anhydrous y-oxo-butanoic acid in 10 mL of chloroform at -20 °C. To this mixture 0.75 mL (5.3 mmol) of isobutyl chloroformate was added dropwise with stirring and exclusion of moisture. After 30 min stirring at -20 °C 1.4 g (7 mmol) of dibenzylamine was added. Stirring was continued for 3 h while slowly warming the t mixture to room temperature. After rota-evaporation of the solvent the crude product was I extracted with ether. Concentration of the etheric solution afforded 1.14 g (45.7%) of crystalline 1.1,5a, mp 84 - 85 °C (EtOH/H20). 

Deduce structures for the pyrones formed by the following sequences (i) PhCOCH3 with PhC C02Et in the presence of NaOEt (ii) butanoic acid heated with PPA at 200 °C (iii) n-BuC0CH2C02H with carbonyl diimidazole (iv) PhCOCH2COCH3 with excess NaH then methyl 4-chlorobenzoate (v) CH3COCH=CHOMe with KOt-Bu and PhCOCl. 

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