Triethylamine carbonyl group

Acyl derivatives of azoles containing two different environments of nitrogen atoms can rearrange. For example, 1-acyl-1,2,3-triazoles are readily isomerized to the 2H-isomers in the presence of triethylamine or other bases the reaction is intermolecular and probably involves nucleophilic attack by N-2 of one triazole on the carbonyl group attached to another (74AHC(16)33). 

With more strongly basic tertiary amines such as triethylamine, another mechanism can come into play. It has been found that wften methanol deuterated on oxygen reacts with acyl chlorides in the presence of triethylamine, some deuterium is found a to the carbonyl group in the ester... 

However, treatment of 4-chloro-3-nitrocoumarin (81) with 2-mercaptophenol (254) provided the product of displacement of the chlorine atom 263. Treatment of compound 263 with triethylamine gave a mixture from which low yields of 266 and 267 were isolated (92ZOR1489). This fact can be explained by the formation of the o-complex 264. This complex is stabilized by carbonyl group participation and therefore an equilibrium of 263 and 265 can be expected. This is in accordance with the formed products (Scheme 41). A similar situation was described earlier for the reaction of 4,5-dichloropyridazin-6(17/)-one with the disodium salt of 2-mercaptophenol (82JHC1447). 

The mechanism of the reaction, which is of the aldol type, involves the carbonyl group of the aldehyde and an active methylene group of the anhydride the function of the basic catalyst B (acetate ion CH3COO or triethylamine N(C3Hj)3) is to form the anion of the active hydrogen component, i.e., by the extraction of a proton from the anhydride ... 

The application of lithiumtrimethylsilyl acetate for the C-l elongation of aldonolactones has been examined (73). Although the reagent had been successfully used for the alkenation of lactone carbonyl groups (74), in the case of aldonolactones 10b or 25b only insignificant yields of the alkenes, but 30 - 40% of the lactols 49a or 50a, were obtained (73). However, these lactols, alternatively prepared in good yields by a Reformatsky-type reaction (53,54), were readily eliminated to the desired alkenes by simple treatment with methanesulfonyl chloride-triethylamine at 0°. Thus, from 49a or 50a separable E,Z mixtures (76a and 76b, or 77a and 77b, respectively) were obtained in good yields (73). 

Much research has been done on the synthesis of perhalogenated P-sultones. The sulfonation of acyclic fluorovinyl ethers leads to a product that is stable up to slightly above room temperature. Thermolysis decomposes the ring structure under SO2 evolution and formation of acid fluorides and perfluorocyclopropane (Eq. 78). )S-Sultones have been synthesized by addition of sulfonyl chlorides to perhalogenated ketones in the presence of triethylamine. The formation of the l-oxa-2-thiacyclobutane 2,2-dioxides appears to require an activated but sterically unhindered carbonyl group because acetone, chloroacetone, trifluoroacetophenone, and p-nitroaceto-phenone did not yield the desired products. ... 

A very short and elegant synthesis of the 16-rtiembered dilactone ( )-pyrenophorin (515) has been accomplished by the dipolar cycloaddition reaction of a trialkylsilyl nitronate (81TL735). Nitromethane was added to 3-buten-2-one and the carbonyl group of the product reduced with sodium borohydride. The nitro alcohol (511) was converted to the acrylate (512) which was then subjected to a dimerization-cyclization reaction by treatment with chlorotrimethylsilane and triethylamine in dry benzene. Hydrogenation of the mixture of isoxazoline products (513) over palladium on charcoal followed by double dehydration of the intermediate bis-/3-hydroxyketone (514) led to ( )- and meso-pyrenophorin (Scheme... 

The action of triethylamine may cause base-induced reactions, such as a-epimerization of carbonyl compounds isomerization of alkenes into conjugation with carbonyl groups and, elimination in carbonyl compounds posssessing a good-leaving group at the (3-position... 

Trifluoroacetylacetone (152) reacts by a condensation reaction 30 with aromatic aldehydes218 in the presence of piperidine and acetic acid, in benzene. Triethylamine does not catalyse this reaction. Probably, the product 153 is obtained via the carbinolamine (154), which in turn yields the carbonyl group of the aldehyde. Obviously, the tertiary amine cannot displace a proton and the interaction forms a zwitterionic adduct (see 148). 

Alkynyl selenides. Terminal alkynes react with C6H5SeCN in CH2C12 in the presence of CuCN or CuBr and triethylamine to give alkynyl selenides in yields usually >90%. The synthesis is compatible with hydroxyl and ethoxyl carbonyl groups. 

The reaction is deceptively simple—formation of an amide in the presence of base—and you would expect the mechanism to follow what we told you in Chapter 12. But the acyl chloride is, in fact, set up for an ElcB elimination—and you should expect this whenever you see an acyl chloride with acidic protons next to the carbonyl group used in the presence of triethylamine. 

Enaminones. Tertiary amines substituted by a carbonyl group at the P-position undergo dehydrogenation to enaminones when treated with the Pd(ll) complex (1 equiv.) and triethylamine (2 equiv.) in acetonitrile (equation 1). 

The crystal structure of the hydroxyphosphorane (88) prepared by N2O4 oxidation of (87) showed an almost perfect tbp structure with the unit cell containing two molecules of the same helicity connected by H-bonds between the P-OH and carbonyl groups.The phosphorus ester (89), fashioned from two n-butyl tartrate moieties exists in solution due to intramolecular hydrogen bonds. On treatment with triethylamine, however, it forms the triethylammo-nium salt (90) of the corresponding hydroxyphosphorane. The pKa value of (89) was determined to be 7.7 in DMF and 4.4 in DMSO, similar to values for dichloroacetic acid in the same two solvents. ... 

---