Octane carboxylic acids

The correlation of pA, - with a (equivalent to the p/C, of 4-substituted bicyclo[2.2.2]octane carboxylic acid) is linear obeying the equation which could therefore be employed as a secondary definition of o ... 

In 1968 Swain and Lupton [298] tried to stop the proliferation of a scales. They defined field and resonance components and by assuming that any set of g values can be expressed by a weighted cohibination + h, that there is no resonance contribution in the case of 4-substituted bicyclo[2.2.2]octane-carboxylic acids (b = 0), and that there is no resonance contribution of a N (CH3)3 substituent ( = 0). They were able to correlate 43 different electronic parameters with linear combinations of these two parameters (many r values being larger than 0.98), e.g. eqs. 40 and 41. 

Roberts and Moreland [13] provided a means of quantitatively separating resonance effects from polar effects by examining 4-substituted bicyclo[2,2,2] octane carboxylic acids (III) and esters, saturated analogues of p-substituted ben-... 

Triaza - 3 - iminobicyclo(3 2,l)octane carboxylic acid hydrobromide... 

Table 43 [146]. Composition of n-octane carboxylic acids obtained by stoichiometric hydrocarboxylation of n-octenes in presence of Ni(CO) as catalyst...

These are effective high-octane gasoline additive oxygenates. The conversion of isobutane into isopropyl, methyl ketone, or isopentane into isobutyl, methyl ketone is illustrative. In this reaction, no branched carboxylic acids (Koch products) are formed. 

Neo acids are prepared from selected olefins using carbon monoxide and acid catalyst (4) (see Carboxylic Acids, trialkylacetic acids). 2-EthyIhexanoic acid is manufactured by an aldol condensation of butyraldehyde followed by an oxidation of the resulting aldehyde (5). Isopalmitic acid [4669-02-7] is probably made by an aldol reaction of octanal. 

Constitution. When coniine is distilled with zinc dust or heated with silver acetate/ a new base, coiiyrine, CgH N, differing from coniine by six atoms of hydrogen, is formed. This on oxidation yields pyridine-2-carboxylic acid and, since it is not identical with 2-isopropylpyridine, must be 2-propylpyridine (I). When coniine is heated with hydriodic acid at 300° it yields w-octane (II). These and other observations due mainly to A. W. Hofmann, made it clear by 1885 that coniine was probably a-propylpiperidine (III), and this has been amply confirmed by other reactions of the alkaloid and by syntheses. Thus, Wolffenstein showed that on oxidation with hydrogen peroxide, coniine is converted into amino-w-propylvaleraldehyde (IV) ... 

Another approach to evaluating cri was taken by Roberts and Moreland,who defined inductive substituent constants in terms of the acid dissociation constants of 4-substituted bicyclof2.2.2]octane-l-carboxylic acids, 3. 

The solid state structure of (3>S,8 Sj-10-(8-amino-6-azaspiro[3,4]octan-6-yl)-9-fluoro-3-methyl-7-oxo-2,3-dihydro-7//-pyrido[l,2,3-dfe]-l,4-benzoxa-zine-6-carboxylic acid (218) was determined by X-ray diffraction study (98CPB1710). The structure of 6,10-dihydropyrido[2,l-c][l,4]benzoxazine-6,10-dione 219 was established by X-ray diffraction analysis. It contains a crystal solvate with /j-xylene (99MI40). 

B. exo-cis-Bicyclo[3.3.0]octane-2-carboxylic acid. A mixture of 100 g. (0.440 mole) of 2-(trichloromethyl)bicyclo[3.3.0]octane and 500 ml. of 85% phosphoric acid is put into a 1-1. three-necked flask equipped with a mechanical stirrer, a reflux condenser, and a thermometer. The mixture is stirred and heated at 150° for 16 hours, during which time it evolves hydrogen chloride and darkens. The product is then allowed to cool and is poured into a separatory funnel. One liter of water is added and the resulting mixture is extracted with four 250-ml. portions of ether. The combined ether extract is then extracted with four 250-ml. portions of 2% aqueous sodium hydroxide (Note 9), and the resulting alkaline extract is washed with 100 ml. of ether to remove any neutral material (Note 10). The alkaline extract is acidified (to pH 2-3) with concentrated hydrochloric acid, and the oil which precipitates is extracted with three 250-ml. portions of ether. The resulting ether extract is dried with 15 g. of magnesium sulfate, filtered, and evaporated at 50° (30 mm.). The residue is then distilled at reduced pressure to obtain 29-32 g. 

As a first step in the prepartion of polymers patterned after the repeating unit of nonactin 56, Moore and Kelley53 synthesized 3,8-dioxabicyclo[3.2.1 ]octan-2-one 57 and its corresponding polyester 58. The monomer was prepared from 5-hydroxy-methylpyran-2-carboxylic acid in overall yield of 20%. It was heated with a catalytic amount of tert-butoxytitanate under nitrogen for 3 hr at 100 °C. The temperature... 

Then, the examples from Reference 23, that focus on retention of the selected binary mixtures of the test analytes (one comprising carboxylic acid and ketone and the other made of alcohol and ketone), chromatographed under the deliberately mild working conditions (microcrystalline cellulose was used as adsorbent and either decalin or n-octane as the monocomponent mobile phase) will be discussed. One of the test solutes in each binary mixture (either acid or alcohol) can be viewed as... 

Carboxylic acids can also be protected as orthoesters. Orthoesters derived from simple alcohols are very easily hydrolyzed, and the 4-methyl-2,6,7-trioxabicyclo[2.2.2]octane structure is a more useful orthoester protecting group. These... 

The high selectivity that the system shows to pyrazine 20 compared to the stronger base pyridine, indicates that the diamine is chelated between the carboxylic acid functions as in 21. Spectroscopic evidence in the form of upfield shifts in the NMR spectra of the complexes supports such structures. Not only aromatic diamines are accommodated but also aliphatics such as l,4-diazabicyclo[2.2.2]octane (DABCO) in complex 22. Typically, exchange rates into and out of these complexes are such that they appear fast on the NMR time scale at ambient temperature, but exchange can be frozen out at low temperatures20. For DABCO, an activation barrier of 10.5 kcal M 1 was observed at Tc = 208 °K. 

A common procedure in C-C-bond formation is the aldol addition of enolates derived from carboxylic acid derivatives with aldehydes to provide the anion of the [5-hydroxy carboxylic acid derivative. If one starts with an activated acid derivative, the formation of a [Mac lone can follow. This procedure has been used by the group of Taylor [137] for the first synthesis of the l-oxo-2-oxa-5-azaspiro[3.4]octane framework. Schick and coworkers have utilized the method for their assembly of key intermediates for the preparation of enzyme inhibitors of the tetrahydrolipstatin and tetrahydroesterastin type [138]. Romo and coworkers used a Mukaiyama aldol/lac-tonization sequence as a concise and direct route to 3-lactones of type 2-253, starting from different aldehydes 2-251 and readily available thiopyridylsilylketenes 2-252 (Scheme 2.60) [139]. 

Trichloroacetyl fluoride, 45, 6 2-(Trichloromethyl)bicyclo[3.3.0]octane, from reaction of chloroform and cib,o i-l,5-cyclooctadiene, 47,10 hydrolysis with phosphoric acid to c.ro-m-bicyclo[3.3.0]octane-2-carboxylic acid, 47, 11 1,1,3-Trichloro- -nonane, 46,104 Tricyclo[2.2.1,02 6]heptan-3-ol, 46,... 

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