Acids reactions with

An ethereal solution of diazomethane free from alcohol may be prepared as follows such a solution is required, for example, in the Amdt-Eistert reaction with acid chlorides (compare Section VI,17). In a 100 ml. longnecked distilling flask provided with a dropping funnel and an efficient downward condenser, place a solution of 6 g. of potassium hydroxide in... 

Chemical ingenuity in using the properties of the elements and their compounds has allowed analyses to be carried out by processes analogous to the generation of hydrides. Osmium tetroxide is very volatile and can be formed easily by oxidation of osmium compounds. Some metals form volatile acetylacetonates (acac), such as iron, zinc, cobalt, chromium, and manganese (Figure 15.4). Iodides can be oxidized easily to iodine (another volatile element in itself), and carbonates or bicarbonates can be examined as COj after reaction with acid. 

The common treatment methods are acidification, neutralization, and incineration. When oxahc acid is heated slightly in sulfuric acid, it is converted to carbon monoxide, carbon dioxide, and water. Reaction with acid potassium permanganate converts it to carbon dioxide. Neutralization with alkahes, such as caustic soda, yields soluble oxalates. Neutralization with lime gives practically insoluble calcium oxalate, which can be safely disposed of, for instance, by incineration. 

Reaction with Acids. Under anliydrous conditions, mono- and diethanolamines and isopropanolaniines fomi carbamates with carbon dioxide (2,3). 

Reaction with Acid Anhydrides. Below room temperature, acid anhydrides react with alkanolamines to produce amides, which partially rearrange to esters on warming to room temperature or slighdy above. 

Chemical Properties The formation of salts with acids is the most characteristic reaction of amines. Since the amines are soluble in organic solvents and the salts are usually not soluble, acidic products can be conveniendy separated by the reaction with an amine, the unshared electron pair on the amine nitrogen acting as proton acceptor. Amines are good nucleophiles reactions of amines at the nitrogen atom have as a first step the formation of a bond with the unshared electron pair of nitrogen, eg, reactions with acid anhydrides, haUdes, and esters, with carbon dioxide or carbon disulfide, and with isocyanic or isothiocyanic acid derivatives. 

Reactions with Acids. Oigaiiic acids form acylates when heated with tetraalkyl titanates. Best results ate obtained using only one or two moles of acid, as attempts to force the reaction with three or four moles of acid can yield polymers. 

The methylhydrazone of acetophenone (112) underwent ready reaction with n-butyl-lithium giving the dianion (113) reaction with acid derivatives such acid chlorides or esters resulted in pyrazole (114) formation whereas with aldehydes, pyrazolines were obtained (76SC5). With dichloromethyleneiminium salts (115), 5-dimethylaminopyrazoles... 

Methylvinyldiazirine (199) rearranges at room temperature in the course of some days. Formation of the linear isomer is followed by electrocyclic ring closure to give 3-methyl-pyrazole. The linear diazo compound could be trapped by its reaction with acids to form esters, while the starting diazirine (199) is inert towards acids (B-71MI50801). 

Isoxazolidine, 2-(trimethyIsiIyloxy)-5-methoxycarbonyl-reactions with acids, 6, 47... 

H-Pyran, 2-alkoxy-4-methyl-2,3-dihydro-conformation, 3, 630 4H-Pyran, 2-amino-IR spectra, 3, 593 synthesis, 3, 758 4H-Pyran, 4-benzylidene-synthesis, 3, 762 4H-Pyran, 2,3-dihydro-halogenation, 3, 723 hydroboration, 3, 723 oxepines from, 3, 725 oxidation, 3, 724 reactions, with acids, 3, 723 with carbenes, 3, 725 4H-Pyran, 5,6-dihydro-synthesis, 2, 91 4H-Pyran, 2,6-diphenyl-hydrogenation, 3, 777 4H-Pyran, 6-ethyl-3-vinyl-2,3-dihydro-reactions, with acids, 3, 723 4H-Pyran, 2-methoxy-synthesis, 3, 762 4H-Pyran, 2,4,4,6-tetramethyl-IR spectra, 3, 593 4H-Pyran, 2,4,6-triphenyl-IR spectra, 3, 593... 

It would thus appear that O acylation is the normal course of the acylation of enamino ketones. Surprisingly the enamino ketones 49 and 50 undergo reaction with acid chlorides not having an a-hydrogen (e.g., benzoyl and pivalyl chlorides) to give the products of C acylation (133). 

Preparation of pure K2O2, Rb202 and CS2O2 by this route is difficult because of the ease with which they oxidize further to the superoxides MO2. Oxidation of the metals with NO has been used but the best method is the quantitative oxidation of the metals in liquid ammonia solution (p. 78). The peroxides can be regarded as salts of the dibasic acid H2O2. Thus reaction with acids or water quantitatively liberates H2O2 ... 

Free nicotinic acid can exist in neutral (21) and in zwitterion forms (22). On reaction with acid either form is converted into the same... 

Normal Fischer esterification of tertiary alcohols is unsatisfactory because the acid catalyst required causes dehydration or rearrangement of the tertiary substrate. Moreover, reactions with acid chlorides or anhydrides are also of limited value for similar reasons. However, treatment of acetic anhydride with calcium carbide (or calcium hydride) followed by addition of the dry tertiary alcohol gives the desired acetate in good yield. 

The most important group of derivatives for the amino function (Fig. 7-4) is the carbamate group, which can be formed by reactions with acids, acid chlorides or acid anhydrides. A series of chlorides as 2-chloroisovalerylchloride [1], chrysanthe-moylchloride [2] and especially chloride compounds of terpene derivatives (cam-phanic acid chloride [3], camphor-10-sulfonyl chloride [4]) are used. The a-methoxy-a-trifluoromethylphenylacetic acid or the corresponding acid chloride introduced by Mosher in the 1970s are very useful reagents for the derivatization of amines and alcohols [5]. 

On reaction with acid, 4-pvrone is protonated on the carbonyl-group oxygen to give a stable cationic product. Using resonance structures and the Hiickel 4n 4- 2 rule, explain why the protonated product is so stable. 

Epoxides can also be opened by reaction with acids other than H30+. If anhydrous HX is used, for instance, an epoxide is converted into a trans halohydrin. 

Lmine(s)—cont d primary. 916 properties of, 920 purification of. 923-924 pyramidal inversion in, 919-920 reaction with acid anhydrides, 807 reaction with acid chlorides, 803-804... 

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