Weak organic base

Because tertiary alcohols are so readily converted to chlorides with hydrogen chlo nde thionyl chlonde is used mainly to prepare pnmary and secondary alkyl chlondes Reactions with thionyl chlonde are normally carried out m the presence of potassium carbonate or the weak organic base pyndme... 

Acyl chlorides react with carboxylic acids to yield acid anhydrides When this reaction is used for preparative purposes a weak organic base such as pyridine is normally added Pyridine is a catalyst for the reaction and also acts as a base to neutralize the hydrogen chloride that is formed... 

For this specific task, ionic liquids containing allcylaluminiums proved unsuitable, due to their strong isomerization activity [102]. Since, mechanistically, only the linkage of two 1-butene molecules can give rise to the formation of linear octenes, isomerization activity in the solvent inhibits the formation of the desired product. Therefore, slightly acidic chloroaluminate melts that would enable selective nickel catalysis without the addition of alkylaluminiums were developed [104]. It was found that an acidic chloroaluminate ionic liquid buffered with small amounts of weak organic bases provided a solvent that allowed a selective, biphasic reaction with [(H-COD)Ni(hfacac)]. 

The value of is reasonable for a weak organic base. The final answer has two significant digits, consistent with the two decimal places in the given pH. 

Lithium Salts Based on Heterocyclic Anions. Lithium salts based on organic anions where the formal charge is delocalized throughout substituted heterocyclic moieties were also reported sporadically, which included, for example, lithium 4,5-dicyano-l,2,3-triazolate ° and lithium bis(trifluoro-borane)imidazolide (Lild). ° The former was developed as a salt to be used for polymer electrolytes such as PEO, and no detailed data with respect to electrochemistry were provided, while the latter, which could be viewed as a Lewis acid—base adduct between LiBp4 and a weak organic base, was intended for lithium ion applications (Table 13). 

Chen and Gao studied the use of oscillopolarographic titration, and reported a direct titration of the salts of weak organic bases (or acids) in aqueous solution [61]. In their work, they included the determination of procaine by an oscillopolarographic titration method. 

Phenylenediamines are relatively weak organic bases and can cause bums if left on the skin for more than a few minutes. Their dark color makes them undesirable for use in fuels or petroleum fractions which have Saybolt color specifications >+15. Because of their alkaline nature, they may also interact with any acidic compounds which may be present in the fuel or in tank-bottom water. Under extreme conditions, this interaction could result in a reduction or loss in performance of the PDA antioxidant. 

Hull and Conant in 1927 showed that weak organic bases (ketones and aldehydes) will form salts with perchloric acid in nonaqueous solvents. This results from the ability of perchlonc aad in nonaqueous systems to protonate these weak bases. These early investigators called such a system a superacid. Some authorities believe that any protic acid that is stronger than sulfunc aad (100%) should be typed as a superaad. Based upon this criterion, fluorosulfuric arid and trifluoro-methanesulfonic acid, among others, are so classified. Acidic oxides (silica and silica-aluminai have been used as solid acid catalysts for many years. Within the last few years, solid acid systems of considerably greater strength have been developed and can he classified as solid superacids. 

The end point in an acid-base titration can be determined either by an acid-base indicator or by means of a potentiometer (or a pH meter). An acid-base indicator is a weak organic acid or a weak organic base which can be written as... 

Aniline, C6H5NH2, is a weak organic base in aqueous solutions. Suggest a solvent in which aniline would become a strong base. 

Neutral acid HA is more soluble in organic solvents than anionic A-Fora neutral weak organic base B... 

In contrast to the case of HMPC, most lipases hydrolyze the racemic acetate of CPBA 9 to give a mixture of the insecticidally active (S)-CPBA 2 and the (R)-acetate 1J). Thus, the desired (S)-CPBA J2 could be separated from the (R)-acetate 10 by means of a continuous counter-current extraction using n-heptane solvent at 80°C. However, it is important to utilize the recovered (R)-acetate W for an efficient process. Fortunately, since the proton of the asymmetric carbon of the cyanohydrin acetate is labile, the antipodal (R)-acetate is easily racemized by treatment with weak organic base such as triethylamine without any side reactions. The racemized acetate J9 thus obtained was recycled as shown in Figure 6. Therefore, all of the racemic acetate 9 was converted to the desired (S)-CPBA 2 in this recycling process. The (S)-CPBA 2 obtained was esterified with (S)-2-(4-chlorophenyl)-3-methylbutyryl chloride to produce the most insecticidally active stereoisomer V2 of fenvalerate, namely esfenvalerate. The relative biocidal activities between... 

It has also been shown, that the interaction of one molecule of acid (HBr) with one molecule of a weak organic base (e.g. THF) in chlorinated hydrocarbons leads pre-(tominantly to the formatfon of a hydrogen bonded complex. A second molecule of the tese is needed in order to convert this complex into the secondary oxonium ion. However, the equilibrium constant of the ionization reaction is stfll low ... 

Under direct irradiation conditions in solvents of low polarity there is no observable reaction. In polar solvents, using ester (132), a slow deconjugation occurs resulting in the formation of (135) this process can be speeded up by the inclusion of a weak organic base, trans-cis Isomerization of ester (133) can compete with the production of (136) via the slow deconjugation process, and unsymmetrically substituted esters such as (134) provide another problem, viz. the possibility of formation of two types of deconjugation product, (137) and (138), as well as that from trans-cis isomerization. Some... 

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