Epoxides reaction with amines

The most important Lewis bases are tertiary amines or polyamines converted into tertiary amines upon reaction with epoxide groups. 

The second type of reaction concerns the use of hydroxymethyl or, more frequently, alkoxymethyl derivatives of melamine, that is, a multifunctional amine, in aminomcthylation (or transaminomethylation) reactions. Crosslinked epoxy resins are also obtained by reaction with epoxides (Fig. 188). - -... 

Overman and Flippin utilized diethylaluminum amides for facile aminolysis of epoxides [71], The procedure involved treating a primary or secondary amine in CH2CI2 with EtsAl (1 equiv.) at room temperature for 30 min, then reaction with epoxide (1 equiv.) overnight. Hydrolysis of the resulting amino aluminate eventually afforded the /8-amino alcohol product in good yield. Aminolysis of cyclopentene oxide with diethylaluminum anilide is shown in Sch. 43 as a typical example. 

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). 

Etherification (hydroxyl reaction with epoxide) has a high activation energy, so it occurs only at elevated tempemtures and is catalysed by teriary amines. 

Some of the major copolymerization reactions of isocyanates are shown in Scheme 2. Only the reaction with epoxides is discussed in this chapter. The reaction with polyols to give polyurethanes and with amines to give polyureas is discussed in Vol. I of this series [2]. Ulrich [2a] has briefly reviewed these and other reactions and this review should be consulted for additional material and references. 

Importantly, for a particular application, and where the metals to be joined have been specified, an overall metal bonding system should be considered. Typically, this will include selection of a suitable adhesive and possibly primer or coupling agent in combination with appropriate methods of surface preparation or pre-treatment. Organofunctional silanes (see Silane adhesion promoters) are commonly used coupling agents, which have been demonstrated to provide covalent chemical bonds with steel or aluminium surfaces and possess epoxide or amine functionality for reaction with Epoxide adhesives. 

Ammonia and amines react with epoxides with the same stereospecificity as anionic nucleophiles. Draw a sawhorse or Newman projection formula for the product of the reaction shown, clearly showing the stereochemistry at both chirality centers. What are the Cahn-lngold-Prelog R,S descriptors for these chirality centers in the reactant and the product ... 

Bis(trimethylsilyl)monoperoxysulphate, being non-acidic, is preferential to Caro s acid as a reagent for Baeyer-Villiger oxidations. j8-Aryloxyethyl esters can be prepared from aryl alkanoates in good yields by reactions with epoxides at 140—170 °C in the presence of an amine. ... 

Close examination of the individual spectra indicate that the cycloaliphatic diamine shows a strong preference for the primary amine reaction. With an excess of activator the primary amine reaction dominates resulting in a single exotherm. In the under-stoichiometric mix, excess epoxide groups remain after the majority of the primary amine has been consumed. The less reactive secondary amine apparently... 

Primary and secondary amines also react with epoxides (or in situ produced episulfides )r aziridines)to /J-hydroxyamines (or /J-mercaptoamines or 1,2-diamines). The Michael type iddition of amines to activated C—C double bonds is also a useful synthetic reaction. Rnally unines react readily with. carbonyl compounds to form imines and enamines and with carbo-tylic acid chlorides or esters to give amides which can be reduced to amines with LiAlH (p. Ilf.). All these reactions are often applied in synthesis to produce polycyclic alkaloids with itrogen bridgeheads (J.W. Huffman, 1967) G. Stork, 1963 S.S. Klioze, 1975). 

The zwitterion (6) can react with protic solvents to produce a variety of products. Reaction with water yields a transient hydroperoxy alcohol (10) that can dehydrate to a carboxyUc acid or spHt out H2O2 to form a carbonyl compound (aldehyde or ketone, R2CO). In alcohoHc media, the product is an isolable hydroperoxy ether (11) that can be hydrolyzed or reduced (with (CH O) or (CH2)2S) to a carbonyl compound. Reductive amination of (11) over Raney nickel produces amides and amines (64). Reaction of the zwitterion with a carboxyUc acid to form a hydroperoxy ester (12) is commercially important because it can be oxidized to other acids, RCOOH and R COOH. Reaction of zwitterion with HCN produces a-hydroxy nitriles that can be hydrolyzed to a-hydroxy carboxyUc acids. Carboxylates are obtained with H2O2/OH (65). The zwitterion can be reduced during the course of the reaction by tetracyanoethylene to produce its epoxide (66). 

Primary cycloaUphatic amines react with phosgene to form isocyanates. Reaction of isocyanates with primary and secondary amines forms ureas. Dehydration of ureas or dehydrosulfuri2ation of thioureas results in carhodiimides. The nucleophilicity that deterrnines rapid amine reactivity with acid chlorides and isocyanates also promotes epoxide ring opening to form hydroxyalkyl- and dihydroxyalkylaniines. Michael addition to acrylonitrile yields stable cyanoethylcycloalkylarnines. 

AH of the amine hydrogens are replaced when MDA or PMDA reacts with epoxides to form amine based polyols. These polyols can be used in reactions with isocyanates to form urethanes or with additional epoxide to form cross-linked thermo set resins. 

General Reaction Chemistry of Sulfonic Acids. Sulfonic acids may be used to produce sulfonic acid esters, which are derived from epoxides, olefins, alkynes, aHenes, and ketenes, as shown in Figure 1 (10). Sulfonic acids may be converted to sulfonamides via reaction with an amine in the presence of phosphoms oxychloride [10025-87-3] POCl (H)- Because sulfonic acids are generally not converted directiy to sulfonamides, the reaction most likely involves a sulfonyl chloride intermediate. Phosphoms pentachlotide [10026-13-8] and phosphoms pentabromide [7789-69-7] can be used to convert sulfonic acids to the corresponding sulfonyl haUdes (12,13). The conversion may also be accompHshed by continuous electrolysis of thiols or disulfides in the presence of aqueous HCl [7647-01-0] (14) or by direct sulfonation with chlorosulfuric acid. Sulfonyl fluorides are typically prepared by direct sulfonation with fluorosulfutic acid [7789-21-17, or by reaction of the sulfonic acid or sulfonate with fluorosulfutic acid. Halogenation of sulfonic acids, which avoids production of a sulfonyl haUde, can be achieved under oxidative halogenation conditions (15). 

Mechanisms for reaction of tertiary amines with epoxides are discussed in References 16 and 17. 

Group of plastics composed of resins produced by reactions of epoxides or oxiranes with compounds such as amines, phenols, alcohols, carboxylic acids, acid anhydrides and unsaturated compounds. 

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