Tertiary amines reactions with

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). 

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). 

This reaction type has been intensely studied °. The application of highly polar solvents, catalysis with tertiary amines" or with acids mesomeric stabilization of intermediate carbenium ions " (allylic and benzylic systems propargylic systems" ) as well as derivatives of sulfinic acids with increasing acidity - usually indicate an ionic pathway (intra- and/or inter-molecular) ... 

The reductive coupling of of dienes containing amine groups in the backbones allows for the production of alkaloid skeletons in relatively few steps [36,46,47]. Epilupinine 80 was formed in 51% yield after oxidation by treatment of the tertiary amine 81 with PhMeSiEh in the presence of catalytic 70 [46]. Notably, none of the trans isomer was observed in the product mixture (Eq. 11). The Cp fuMcTIIF was found to catalyze cyclization of unsubstituted allyl amine 82 to provide 83. This reaction proceeded in shorter time and with increased yield relative to the same reaction with 70 (Eq. 12) [47]. Substitution of either alkene prevented cyclization, possibly due to competitive intramolecular stabilization of the metal by nitrogen preventing coordination of the substituted olefin, and resulted in hydrosilylation of the less substituted olefin. 

Summary New lyophilic cationic silicone surfactants have been synthesized by direct quatemization of halogenated siloxanyl precursors or by transformation of these precursors into tertiary amines with a subsequent quatemization step. After transformation of the precursors into secondary amines, reaction with maleic anhydride and neutralization, new anionic products were obtained. 

The dealkylative functionalization of tertiary amines 23 with electron deficient heteroaryl chlorides including triazinyl chloride 24 has been published <06TL2229>. Efficient and practical reaction conditions were determinated for a range of substrates. 

The reaction of tertiary amine oxides with nitrous acid has also been shown to produce N-nitroso compounds. The mechanism for the amine oxides is similar to that for the tertiary amines (26). 

Acid chlorides are very reactive, and they readily react with ammonia, primary amines, or secondary amines to form an amide. Figure 12-26 illustrates the reaction of an acid chloride with ammonia. Replacing one or two of the hydrogen atoms of ammonia with an organic group will result in an N-substituted amide. Tertiary amines react with acid chlorides to form a carboxylic acid and an ammonium salt. 

The palladium-catalyzed amination reaction with a monofunctional primary amine 167 effects i / -diarylation to afford the tertiary amine polymers 168. Hence, polycondensation of 167 with bifunctional arylene dihalides leads to 168 (Equation (81)). Polycondensation of a primary amine bearing an azobenzene moiety with dibromides in the presence of Pd2(dba)3 (2.5mol%)- Bu3P (P/Pd = 3 l) and NaO Bu at 100°G for 24h in toluene gives 168 in 81-93% yields, as reported by Kanbara. 

Tertiary amines react with phosgene to give symmetrical tetrasubstituted ureas (Eq. 28). (See Table II.) This reaction probably involves the intermediate... 

Later studies on the ECF of tetraalkyl ammonium salts, known to be very stable towards electrochemical oxidation, showed that these reactions proceeded similarly to tertiary amines, but with increased formation of gaseous cleavage products [183]. 

It was mentioned at the beginning of this chapter that alkaloids were among the first catalysts to be used for asymmetric hydrocyanation of aldehydes. More recent work by Tian and Deng has shown that the pseudo-enantiomeric alkaloid derivatives 5/6 and 7/8 catalyze the asymmetric addition of ethyl cyanoformate to aliphatic ketones (Scheme 6.6) [50]. It is believed that the catalytic cycle is initiated by the alkaloid tertiary amine reacting with ethyl cyanoformate to form a chiral cyanide/acylammonium ion pair, followed by addition of cyanide to the ketone and acylation of the resulting cyanoalkoxide. Potentially, the latter reaction step occurs with dynamic kinetic resolution of the cyano alkoxide intermediate... 

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). 

Reaction of the tertiary amine (390) with three equivalents of dibenzoyldiimide yielded the pyrido-1,3,4-oxadiazine (391) (65%) via the intermediacy of an enamine generated from the amine (390) <77 JCS(P2) 1977 >. 

Trialkyl- and triarylperoxyarsoranes have been obtained by the reaction of triorganyl dihaloarsoranes with either an alkylhydroperoxide in the presence of a tertiary amine or with the sodium salt of alkylhy-droperoxides. These can also be prepared by the reaction between amino halides R3As(NH2)X and an alkylhydroperoxide or by the following exchange reactions ... 

In the reductive alkylation of (V-ethylcyclohexylamine with cyclohexanone at 160°C and 4.1-5.2 MPa H2, platinum gave only a 27% conversion of the starting secondary amine and 22% yield of the corresponding tertiary amine, compared with 52% conversion and 42% yield of the tertiary amine with platinum sulfide. Thus, in general, platinum sulfide, or other platinum metal sulfides, have been shown to be the catalysts of choice when more hindered reagents require more severe reaction conditions. 

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

Tertiary amines react with oxygen in the presence of platinum to give antides showing a strong preference for reaction at methyl groups. For example, oxidation of trimethylamine gives )V,iV-dimethyl-formamide in 74% yield, and /V-methylcyclohexylamine yields )V-formylcyclohexylairune in quantitative yield. 

The substitution reaction by ammonia and other amines can give rise to complex mixtures of primary, secondary and tertiary amines, together with quaternary ammonium salts (see Scheme 2.4). The separation of these by chemical means, as opposed to distillation or chromatography, is discussed in the section on amines. 

Three types of product can be obtained from the reaction of amines with carbon monoxide, depending on the catalyst. (1) Both primary and secondary amines react with CO in the presence of various catalysts [e.g., Cu(CN)2, Me3N-H2Se, rhodium or ruthenium complexes] to give V-substituted and V,A-disubstituted formamides, respectively. Primary aromatic amines react with ammonium formate to give the formamide. Tertiary amines react with CO and a palladium catalyst to give an amide. (2) Symmetrically substituted ureas can be prepared by treatment of a primary amine (or ammonia) with CO " in the presence of selenium or... 

Ketenes can be prepared by treatment of acyl halides with tertiary amines or with NaH and a crown ether. The scope is broad, and most acyl halides possessing an a hydrogen give the reaction, but if at least one R is hydrogen, only the ketene dimer, not the ketene, is isolated. However, if it is desired to use a reactive ketene in a reaction with a given compound, the ketene can be generated in situ in the presence of the given compound. ... 

In the presence of the radical substitution promoter [Fe2(CO)4()u,-SR)i(PPh3)2], tertiary amines react with transition metal carbonyl clusters under exceptionally mild conditions. Modified allenyl and allylic clusters similar to those described earlier have been isolated from such reactions. Two distinct types of products have been isolated (i) those involving the elimination of an alkyl group and (ii) those involving C-C coupling reactions. The product formation described in Scheme 31 was preceded by amine coordination, C-H activation, C-N cleavage, carbene-amine complex formation, transamination, and C-C coupling (6Ia.h)- Such processes are of interest in the area of hydrodenitrification (6/c). 

The use of a-cyanoamines in place of their less stable iminium ion precursors often results in high product yields in the Pictet-Spengler and other ring closure reactions. Thus, the Polonovski-derived a-cyanoamine (39a) cyclized to (40) in 84% yield, whereas reaction of the tertiary amine (39b) with mercury(n) acetate was unsuccessful (equation 13). The conversion of unstable S,6-dihydropyridinium salts (41), obtained by reaction of tetrahydropyridine IV-oxides with trifluoroacetic anhydride, into the stable, synthetically versatile tetrahydropyridine-2-carbonitiile (42) is another area in which use of this methodology has met with particular success (equation 14). ... 

Polonovski reaction. This reaction consists in the reaction of the N-oxide of a tertiary amine (1) with acetic anhydride to form the N-acylated secondary amine (2) as the major product and the deaminated ketone (3) as minor product ... 

COMPARISON OF TERTIARY AMINE (DMCHA) WITH ORGANOTIN (DBTDL) CATALYSTS IN THE REACTION OF PHENOL AND BENZYL ALCOHOL WITH PHENYL ISOCYANATE IN DIOXANE AT 25°C... 

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