Tertiary amines reactions

Aliphatic Alcohols and Thiols. Ahphatic alcohols on reaction with chloroformates give carbonates and hydrogen chloride. Frequendy, the reaction proceeds at room temperature without a catalyst or hydrogen chloride acceptor. However, faster reactions and better yields are obtained in the presence of alkaU metals or their hydroxides, or tertiary amines. Reactions of chloroformates with thiols yield monothiolocarbonates (14). 

In addition to quenching excess hydride, the acidification and subsequent extraction steps remove pseudoephedrine and any tertiary amine reaction by-product the latter is otherwise difficult to remove by column chromatography. 

Of commercial interest is the direct reaction of alcohols with ammonia at elevated pressures and temperatures in the presence of a dehydrating catalyst such as alumina gel. This process is known as ammonolysis and gives a mixture of primary, secondary and tertiary amines (Reaction XXVII). 

However, above 100°C the ferf-butyl analogue gives pure BeH2. With tertiary amines, reactions of the following types may occur ... 

In addition to the formation of silyl enol ethers, isomerization of epoxides to allylic alcohols is another highly typical transformation performed by combination of a silicon Lewis acid with a tertiary amine. Reaction with la was examined, and its scope and limitation reported, by Noyori [61]. Epoxide 44 can be successfully converted into the corresponding allyl silyl ether 45 (Sch. 34). 

Quarternary Zeolite Tertiary amine Reaction 13C NMR shifU... 

The following reaction network represents the equilibrium reactions taking place in a system of tertiary amine -H2O - H2S - CO2, as shown by (Austegen et al., 1991) [17]. It can be generalized to all similar tertiary amine reactions including TEA ... 

An ionic reaction mechanism such as this may be expected to cause charging problems on an electrode surface. This is the case, in fact, as was seen in the ionic conductivity experiments of Part II. An increase in ionic conductivlly was also noted by both Luston and Antoon while studying epoxide-anhydride-tertiary amine reactions. 

More generally, ammonolysis or aminolysis of alkyl halides, and particularly primary alkyl halides, is likely to give rise to mixtures of the primary, secondary and tertiary amines (reactions 19, 20 and 21). The proportions of the three possible amines in such a mixture may be varied by alterations in the relative proportions of the reactants. Where, for example, the primary amine is the desired product, the use of liquid ammonia (to ensure high concentration of ammonia), and also of sodamide (one mole per mole of alkyl halide) in liquid ammonia have been recommended, though some dehydrohalogena-tion of the alkyl halide may occur when sodamide is used (reaction 42). 

Thioxanthones (Table 11) in conjunction with tertiary amines are efficient photoinitiators [140] with absorption characteristics that compare favorably with benzophenones absorption maxima are in the range between 380 and 420 nm (e = lO L moP cm ), depending on the substitution pattern. The reaction mechanism has been extensively investigated by spectroscopic and laser flash photolysis techniques [64,141-143]. It was found that in conjunction with tertiary amines, reactions similar to that of benzophenone-amine systems take place. 

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