Monocarboxylic esters from

Acetylene dicarboxylic esters and (less easily) acetylene monocarboxylic esters replace nitriles from the 4,5-positions of 1,2,4,3-triazaphosphole rings (92) to give carboxyl derivatives of 1,2,3-diazaphospholes, presumably by a cycloaddition/cycloreversion mechanism, R/R = Me/Ph, SiMej/NMCj <83ZN(B)1484>. 

A continuous distillation process has been studied for the production of high boiling esters from intermediate boiling polyhvdric alcohols and low boiling monocarboxylic aliphatic or aromatic acids. The water of reaction and some of the organic acid were continuously removed from the base of the column. 

The monocarboxylic esters were separated from other acid esters by thin-layer chromatography (TLC) on silica GF254 (Merck) by development in n-heptane-diethyl ether-methanol (80 20 2, v/v/v). TLC plates were visualized under ultraviolet light after spraying with 2,7-dichlorofluorescein, and the mono carboxylic ester band (R = 0.52) was removed and extracted with chloroform. 

The total monocarboxylic esters (mono-AMEs) obtainable from each lithotype are plotted in Figure 3. One readily notes that, while the points seem to be distributed somewhat randomly, the levels of free mono-AMEs are substantially higher than the levels of bound mono-AMEs for every sample. The levels of total mono-AMEs for the light and dark lithotypes appear to be substantially higher than those of the other lithotypes. 

Jenkins (16) has isolated cyclic monocarboxylic and fatty acids as well as aliphatic esters from petroleum distillates and residues of several crudes. Seifert and Howells (17), through an elaborate extraction and separation scheme, have recovered phenols and carboxylic acids with molecular weights of 300 to 400 from the Midway-Sunset crude. The acidic extracts have been shown to give ultra low (< 10 dyne/cm) interfacial tensions when contacted with an alkali aqueous phase. Phenolic components isolated from the crude were found to diminish the interfacial activity of the acidic fraction. 

Fischer made extensive use of the reactions of the sugars with phenylhydrazine, a reagent which he had discovered in 1875. Fischer also oxidised the sugars to mono- and dicarboxylic acids, reduced the carbonyl function to a hydroxyl group, and prepared lactones (cyclic esters) from the monocarboxylic acids. Fischer also used a reaction devised by Heinrich Kiliani (1855-1945) in which the carbon chain of a sugar could be extended. Thus a five-carbon sugar could be converted to two six-carbon sugars because a new asymmetric centre had been added. 

From both economic and ecological points of view, substances derived from esters of monocarboxylic acids sulfonated in the a position form an interesting class of surfactants [1]. The general formula of these a-sulfomonocarboxylic esters, also called a-sulfo fatty acid esters or, in short, a-ester sulfonates, is Rj-CH(S03Me)-C00-R2 (with Rj and R2 = alkyl groups, Me = alkali metal). 

Composition. Rosin is primarily a complex mixture of monocarboxylic acids of alkylated hydrophenanthrene nuclei. These constituents, known as resin acids, represent about 90% of rosin. The resin acids are subdivided into two types, based on their skeletal structure. The abietic-type acids contain an isopropyl group pendent from the carbon numbered 13. The pimaric-type acids have a methyl and vinyl group pendent from the same carbon atom. Figure 1 shows the structure of typical resin acids abietic acid, C20H30O2 (1) is predominant. The remaining 10% of commercial rosin consists of neutral materials that are either hydrocarbons or saponifiable esters. These materials are derived from resin acids by decarboxylation or esterification. 

Kolbe electrolysis is generally useful for the formation of hydrocarbons from monocarboxylic acids and for the preparation of many difunctional compounds as well. A specific illustration is the synthesis of esters of long-chain dicarboxylic adds from monoesters of appropriate dicarboxylic acids (see p. 33). A number of these syntheses are discussed by Fichter.4 In the present preparation, a two-compartment cell is employed to avoid, or at least greatly reduce, undesired reduction of the nitro group at the cathode. It seems likely that the procedure could be adapted to the preparation of other difunctional compounds containing groups that are easily reduced. 

Esters. The monoisobutyrate ester of 2,2,4-trimethyl- 1,3-pentanediol is prepared from isobutyraldehyde in a Tishchenko reaction (58,59). Diesters, such as trimethylpentane dipelargonate (2,2,4-trimethylpentane 1,3-dinonanoate), are prepared by the reaction of 2 mol of the monocarboxylic acid with 1 mol of the glycol at 150—200°C (60,61). The lower aliphatic carboxylic acid diesters of trimethylpentanediol undergo pyrolysis to the corresponding ester of 2,2,4-trimethyl-3-penten- l-ol (62). These unsaturated esters reportedly can be epoxidized by peroxyacetic acid (63). 

Kishner1 studied the reaction of the Orignard reagent sn the ester of cyclopropane monocarboxylic acid, he obtained a compound which ne considered to be cyclopropyldii.iethylcaJbinol.and from this ht obtained an uneaturated hydrocarbon,cyclop/opylmethyl-ethylene, CHg - CH - C CHS The cyclic struc-... 

The amidation of unsaturated acids or esters (not necessarily a,(3 unsaturated ones) leads to derivatives of the corresponding dicarboxylic acids and may serve as a method for the synthesis of dicarboxylic acids from unsaturated monocarboxylic acids (10,13, 14). This reaction of formamide with oc,(3-unsaturated acid derivatives besides being of synthetic value has some interesting aspects as far as free radical chemistry and photochemistry are concerned. We shall start this section in discussing the last point, i.e. the photochemical aspects of the reaction. This point is of primary interest to the synthetic organic chemist, who must be aware of it, otherwise he may fail in his synthetic work purely because of photochemical reasons. 

It can be assumed that the small amount of piperidine in the reaction mixture is completely protonated by malonic acid because piperidine is more basic than pyridine. Hence, only the less basic pyridine is available for the formation of the malonic acid enolate D from free malonic acid and for the formation of the malonic acid dianion from the malonic acid mono-carboxylate C. The pKa value of malonic acid with regard to its C,H acidity should be close to the pKa value of malonic acid diethyl ester (p= 13.3). The pKa value of malonic acid monocarboxylate C with regard to its C,H acidity should be larger by at least a factor 10. Hence, the concentration of the malonic acid enolate D in the reaction mixture must be by many orders of magnitude higher than that of any malonic acid dianion. Due to the advantages associated with this enormous concentration D could be the actual nucleophile in Knoevenagel condensations. 

Chrysanthemum carboxylic acid esters. Chrysanthemum monocarboxylic acid (CMC) and dicarboxylic acid (CDC) esters include the toxic cinerins and pyrethrins from... 

Materials. All monomers were of commercial quality vinyl chloride (VCM), vinyl acetate and VeoVa 10. The latter is a vinyl ester of a saturated monocarboxylic acid with a highly branched structure containing 10 carbon atoms. This monomer is produced by Shell Chemicals. The emulsifier, sodium dodecyl sulphate (SDS), was the commercial material Berol 474 from Berol Kemi, Sweden. NapS 0o supplied by Noury Van der Lande, was used as initiator. The NaHCOq used as buffer and for adjustment of the electrolyte concentration, was Merck p.a. grade. 

The synthetic utility of alkylation of enolates is utilized in the syntheses of malonic ester (3.3) and acetoacetic ester (3.2). For example, carbanion generated from malonic ester undergoes an Sn2 reaction with alkyl halide to yield alkyl-substituted malonic ester. The monosubstituted malonic ester still has an active hydrogen atom. The second alkyl group (same or different) can be introduced in a similar manner. Acid-catalyzed hydrolysis or base-catalyzed hydrolysis of mono- or disubstituted derivative of malonic ester followed by acidification gives the corresponding mono- or disubstituted malonic acid, which on decarboxylation yields the corresponding monocarboxylic acid (Scheme 3.3). 

This study reports the monocarboxylic fatty acid content of a series of brown coal lithotypes from the Latrobe Valley, Victoria, Australia. We have looked both at the solvent-extractable, or free, fatty acids (which include those extractable as esters or intact lipids) and at those that are released upon hydrolysis (saponification) of the residue after solvent extraction. The latter are presumably bound chemically to the coal matrix (kerogen) and are therefore designated as bound acids. The total acids are taken as the sum of the free and bound acids. 

Both monocarboxylates, e.g., Hg(OCCOCl3)2 and HgfOAclj, where OAc is —0C(0)CH3, and dicarboxylates, e.g., Hg succinate can be used. Chiral carboxylates also are employed. Diastereoisomers are isolated from the reaction of s-Bu2Hg and the Hg salt of the monoethyl ester of (d)-tartaric acid . 

Figure 6.- Total Ion Chromatogram of the thermal degradative products obtained after pyrolysis of the HA isolated from the Konin (Poland) brown coal in the presence ot TMAH. Key labels for aromatic compunds are (9) 4-memoxybenzenecarboxylic acid methyl ester, (14) benzenedicarboxylic acid dimethyl ester, (16) 3,4-dimelhoxybenzenecarboxylic acid methyl ester, (17) 3,4-dimethoxybenzeneacetic acid methyl ester, (18) 4-medioxycinnamic acid methyl ester, (19) 3,4,5-trimethoxy-l-ethylbenzene. Key labels for aliphatic compounds are (Cn) monocarboxylic acid methyl esters, (Cn l) unsaturated monocarboxylic acid methyl esters, (Cn) dicarboxylic acid dimethyl esters.

What is the molar mass and possible formula of the ester that is formed from a monocarboxylic acid with molar mass 60 g/mol and a monoalcohol with molar mass 46 g/mol (C 12 g/mol, H 1 g/mol, 0 16 g/mol)... 

Thoria has been used successfully as a catalyst in the synthesis of many organic compounds. Thus both symmetrical and unsymmetrical ketones may be prepared directly from monocarboxylic acids 3 alcohols are converted into ethers or olefines according to the temperature employed benzyl alcohol forms esters with formic, acetic, propionic, isobutyric, and benzoic acids and ammonia and alcohols passed over thoria at 360° yield olefines and primary amines.4... 

Yoshimura et al. [1989] give a lengthy description of their invention, which was primarily aimed at producing film (Table 11.9) particularly suited for shrink wrapping, with many examples and extensive sets of results. The film is made from the following three groups of polymers (i) LDPE and a copolymer of ethylene, either with vinyl ester monomer, or with an unsaturated aliphatic monocarboxylic acid or its aliphatic ester (EVAc being the most desirable copolymer) (ii) one of the... 

---