Chloroform effect phenols

Subsequent investigations have reinforced earlier evidence for the wide occurrence of hydrogen bonding of azines. Bonding of all the monocyclic azines,many substituted azines, and azinones with water, alcohols, and dilute acids has been studied by electronic absorption spectra and the variation of the effect with changes in the position of the substituent noted. Quinolines and acridines with chloroform, alcohols, phenols, carboxylic acids, aniline, and pyrrole show the influence of hydrogen bonding on... 

Reimer, K., Tiemann, F. The effect of chloroform on phenol and especially on the alkaline solution of aromatic oxyacids. Ber. Dtsch. Chem. 

Chlorofonn is too non-polar to dissolve the phenolic compounds under study, but it dissolves many of the monoterpenes, at least to some extent. Because the solubility of some monoterpenes into chloroform was low, different solvent/ solid ratios were tested. These were 50,20,10 and 5 1/kg of dry phloem. The extracts were bright yellow and the strongest colour was with the smallest solvent/solid ratio (51/kg). The colour of the solvent indicated that the solubility of the extractable compounds was not restricting the reaction even with the smallest solvent volume. The taste of the dry samples was evaluated by comparing them to the original phloem sample. The results showed that the mildest taste was in the phloem extracted with a solvent/solid ratio of 50 1/kg and 20 1/kg also had some effect on the taste. The taste of the chloroform-extracted phloem was stabile and it was the same after a week. 

To date, effecting the subsequent reaction chemistry (as hypothesized in Fig. 12.9) has not been possible in our laboratories. There have been indications that reaction of the epoxide quinone methide QM24 in chloroform with acetic acid may have opened the epoxide before rearomatizing the quinone methide moiety, but this is not well authenticated. However, all attempts to add phenols to this epoxide, particularly aimed at producing 8-0-4-ethers PI, have been unsuccessful. Similar reactions using QM25 have also failed. 

Symmetrical and unsymmetrical carbonates have also been obtained from the reaction of chloroformates with alcohols under soliddiquid conditions [55], and the reaction of carbamoyl fluorides with alcohols produces alkyl carbamates [58]. r-Butyloxycarbonylation of alcohols and phenols is effected by trans-esterification of di-r-butyl carbonate under basic phase-transfer catalysed conditions [59]. Yields tend to be high for the reaction with the phenols (>85%), but only moderate with the alcohols (30-81%). 

The solvents most commonly employed are water, ethyl and methyl alcohol, ether, benzene, petroleum ether, acetone, glacial acetic acid also two or three solvents may be mixed to get the desired effect as described later. If you still cannot dissolve the compound, try some of these chloroform, carbon disulfide, carbon tetrachloride, ethyl acetate, pyridine, hydrochloric acid, sulfuric acid (acids are usually diluted first), nitrobenzene, aniline, phenol, dioxan, ethylene dichloride, di, tri, tetrachloroethylene, tetrachloroethane, dichloroethyl ether, cyclohexane, cyclohexanol, tetralin, decalin, triacetin, ethylene glycol and its esters and ethers, butyl alcohol, diacetone alcohol, ethyl lactate, isopropyl ether, etc. 

Anti-implantation effect. Chloroform extracts of the dried leaf, twig, and stem, administered intragastrically to pregnant rats at a dose of 0.58 g/kg for 10 days, were active. The phenolic fraction, at a dose of 0.52 g/kg and methanol extract at a dose of 0.70 g/kg, were active. Water extract, at a dose of 1 g/kg and petroleum ether extract at a dose of 0.38 g/kg, were inactive Anti-tumor activity. Water extract of the dried root, administered intraperitoneally to mice at a dose of 400 mg/kg, was inactive on Leuk (friend virus-solid) and Leuk-L1210. A dose of 500 mg/kg was inactive on sarcoma 180(ASC) - . 

Figure 13.23. Examples of vapor-liquid equilibria in presence of solvents, (a) Mixture of-octane and toluene in the presence of phenol, (b) Mixtures of chloroform and acetone in the presence of methylisobutylketone. The mole fraction of solvent is indicated, (c) Mixture of ethanol and water (a) without additive (b) with 10gCaCl2 in 100 mL of mix. (d) Mixture of acetone and methanol (a) in 2.3Af CaCl2 ip) salt-free, (e) Effect of solvent concentration on the activity coefficients and relative volatility of an equimolal mixture of acetone and water (Carlson and Stewart, in Weissbergers Technique of Organic Chemistry IV, Distillation, 1965). (f) Relative volatilities in the presence of acetonitrile. Compositions of hydrocarbons in liquid phase on solvent-free basis (1) 0.76 isopentane + 0.24 isoprene (2) 0.24 iC5 + 0.76 IP (3) 0.5 iC5 + 0.5 2-methylbutene-2 (4) 0.25-0.76 2MB2 + 0.75-0.24 IP [Ogorodnikov et al., Zh. Prikl. Kh. 34, 1096-1102 (1961)].

Fig. 2.9. Effect of the dielectric constant of the solvent on the fluorescence intensity of DNS-phenol. Solvents (of increasing dielectric constant) hexane dioxane benzene chloroform ethyl acetate acetone and ethanol.

Phenols are smoothly converted into phenolic aldehydes by reaction with chloroform in the presence of base (the Reimer-Tiemann reaction). This overall formylation reaction is of interest in that it involves the generation from chloroform and alkali of the reactive intermediate, dichlorocarbene (2). This effects electrophilic substitution in the reactive phenolate ions giving the benzylidene dichloride (3) which is hydrolysed by the alkaline medium to the corresponding hydroxyaldehyde. The phenolic aldehyde is isolated from the reaction medium after acidification. 

The parent / -f-butylcalix[n] arenes (n = 4, 6, 8) are almost completely insoluble in water. However, their resemblance to crown ethers and spherands makes them interesting from the point of view of applications as phase transfer catalysts (Section 3.8.2). Table 3.20 shows the selectivity of calixarene 3.118 and its hexameric and octameric homologues for the extraction of various metal hydroxides into an organic receiving phase such as chloroform. Fortunately, in aqueous base the calixarenes are sufficiently soluble to act as phase transfer catalysts as a consequence of deprotonation of one of their phenolic hydroxyl groups. This solubility contrasts to [18] crown-6, which is much more effective in neutral solution. 

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