Alkyl amines triethylamine

For alkyl amines, a direct correlation between the steric bulk at the a-carbon and the yield of the reaction was found amines attached to a secondary carbon gave higher yields than amines connected to a tertiary carbon, while amines connected to a quaternary carbon led only to the formation of an amide-carboxylic acid intermediate, rather than the corresponding imide. In the case of amino acids whose ot-carbons are tertiary, a lower temperature was surprisingly required for high NMI selectivity in the first step (40 °C instead of 75 °C). This was explained by the presence of the COOR group, which assists in the collapse of the tetrahedral intermediate precursor to the imide formation. The amino acid derived NMIs were obtained as a mixture of open and closed forms due to the addition of triethylamine in the reaction. At high temperatures this promotes the formation of... 

In an attempt to gain insight into the pharmacophore moiety of the ergot alkaloids, aza-transposed ergolines were synthesized [55] with the nitrogen atom in the 9-position by alkylation-amination of a tricyclic enamine in the presence of ethyl a,a,-bis(dibromomethyl)acetate, triethylamine, and methyl-amine which led to the construction of the azatransposed ergoline. 

With two nitrile groups, the delocalized anion is so stable that even a weak, neutral amine (triethylamine) is sufficiently basic to deprotonate the starting material. Here double alkylation again takes place, in 100% yield note that the electrophile is good at 5 2, and the dipolar aprotic solvent DMSO (like DMF) cannot solvate the enolate anion, making it more reactive. 

Associative Systems. Hydrophobic comonomers were synthesized in the following manner. N-n-octyl, decyl, and dodecylacrylamide were synthesized by the reaction of acryloyl chloride (0.55 M) with the corresponding alkyl amine (0.55 M) in THF at 10 C with triethylamine (0.60 M) present as the acid receptor. Following filtration of triethylamine hydrochloride and evaporation of THF, the crude product was twice recrystallized in acetone at -25 C. The products were characterized by elemental analysis, melting point, FTIR,... 

The effect of chain length is more pronounced in the tertiary alkyl-amines (Table 4), where triethylamine is much more basic than trimethylamine, whilst iV,i T-dimethylethylamine and iV,iV-diethyl-methylamine lie intermediately. There are some anomalies amongst the data for the higher members of this series, and further measurements on them would be of interest. 

Zinc(II) tetraphenylporphyrin (ZnTPP) can be covalently incorporated into the unimer micelle by terpolymerization using a ZnTPP-substituted acrylamide monomer zinc(II) 5-(4-acrylamidophenyl)-10,15,20-triphenyl-porphynate (ZnAATPP) (Scheme 7) [81]. For the terpolymerization, AMPS is used as its triethylamine salt to avoid the risk that the metal is removed from the porphyrin ring under acidic conditions during the terpolymerization. Another advantage for the neutralization of AMPS with an alkyl amine is that the solubility of the electrolyte monomer in organic solvents is significantly increased. 

In recent years there has been some substitution of TDI by MDI derivatives. One-shot polyether processes became feasible with the advent of sufficiently powerful catalysts. For many years tertiary amines had been used with both polyesters and the newer polyethers. Examples included alkyl morpholines and triethylamine. Catalysts such as triethylenediamine ( Dabco ) and 4-dimethyla-minopyridine were rather more powerful but not satisfactory on their own. In the late 1950s organo-tin catalysts such as dibutyl tin dilaurate and stannous octoate were found to be powerful catalysts for the chain extension reactions. It was found that by use of varying combinations of a tin catayst with a tertiary amine... 

Tertiary amines also depolymerize lithium alkyl tetramers and hexamers and can be used to trigger reactions with alkyl halides (Lepley, 1968). However, when triethylamine is used to initiate the butyl... 

The best yields are obtained when the ketene has an electronegative substituent, such as halogen. Simple ketenes are not very stable and must usually be generated in situ. The most common method for generating ketenes for synthesis is by dehydrohalo-genation of acyl chlorides. This is usually done with an amine such as triethylamine.167 Other activated carboxylic acid derivatives, such as acyloxypyridinium ions, have also been used as ketene precursors.168 Ketene itself and certain alkyl derivatives can be generated by pyrolysis of carboxylic anhydrides.169... 

Di-2-pyridyl sulphite (343) (from 2-pyridone and thionyl chloride in the presence of triethylamine) transforms primary aliphatic and aromatic amines RNH2 into N-sulphinylamines RN=S=0 and it dehydrates amides ArCONH2 to aryl cyanides, aldehyde oximes RCH=NOH (R = Cxlf 7. 4-MeOCgH4 or PhCH=CH) to the cyanides RCN and A-alkyl- and TV-ary Iformamides RNHCHO to isocyanides RNC. Aliphatic and aromatic... 

FDMR has also been used to detect the transient radical cations formed from secondary amines by pulse radiolysis. As mentioned earlier this technique has been used to study a variety of systems such as the radical cation of triethylamine. The radical cations of diethylamine, n-propyl amine and f-butylamine, have also been studied25. The results have shown that the FDMR signal is enhanced with increasing alkyl substitution of the amine as in the pyrrolidines (18) and the piperidines (19)25. 

In the presence of diisopropyl(ethyl)amine, tetrachlorosilane reacts with f-butyl hydroperoxide to give 1 1 adduct 9 (equation 16). Alkylperoxydiorganoalkoxysilanes are prepared from the reaction of chlorodiorganooxysilane with alkyl hydroperoxides in the presence of ammonia or organic base such as pyridine or triethylamine (equations 17 and 18). 

The relationship between the structure of the tertiary amine and the intrinsic rate of racemization was clear. This effect has been studied before by Williams,[32 among others. Two families of bases were compared trialkylamines and 4-alkylmorpholines. The trends were most clearly expressed in the experiments using Boc-Ser(OBzl)-NCA. The rate was decreased within each family as the steric bulk of the amine was increased. This result was consistent with the direct enolization mechanism that requires a close approach of the tertiary amine for the abstraction of the a-proton. The rate was much lower with 4-alkyl-morpholines than with trialkylamines because of the decreased basicity of the former (triethylamine and 4-ethylmorpholine have similar structures TEA is actually more hindered). The most favorable results with respect to racemization were obtained when a weak base was combined with a sterically hindered substituent, as with 4-cyclohexylmorpholine. In the case of Boc-Phe-NCA, the same trends were seen, except that racemization by the 4-alkylmorpholines was so slow that the differences within that family were not significant. 

Hosokawa, Murahashi, and coworkers demonstrated the ability of Pd" to catalyze the oxidative conjugate addition of amide and carbamate nucleophiles to electron-deficient alkenes (Eq. 42) [177]. Approximately 10 years later, Stahl and coworkers discovered that Pd-catalyzed oxidative amination of styrene proceeds with either Markovnikov or anti-Markovnikov regioselectivity. The preferred isomer is dictated by the presence or absence of a Bronsted base (e.g., triethylamine or acetate), respectively (Scheme 12) [178,179]. Both of these reaction classes employ O2 as the stoichiometric oxidant, but optimal conditions include a copper cocatalyst. More recently, Stahl and coworkers found that the oxidative amination of unactivated alkyl olefins proceeds most effectively in the absence of a copper cocatalyst (Eq. 43) [180]. In the presence of 5mol% CUCI2, significant alkene amination is observed, but the product consists of a complicated isomeric mixture arising from migration of the double bond into thermodynamically more stable internal positions. 

The C2-symmetrical chiral amine tran.v-(2/ ,6y )-2,6-bis(benzyloxymethyl)piperidine (1), prepared15 from commercially available (S)-2-(benzyloxymethyl)oxirane, has been used in diastereoselective amide alkylations. Thus, the chiral amine of 76% ee is acylated [anhydride or mixed trimethylacetic acid anhydride, 1.2 equivalents of triethylamine and 0.05 equivalents of 4-(dimethylamino)pyridine] and the resulting amide 2 treated with 2.1 equivalents of lithium diisopropylamide at —78 CC to give the enolate. This is then alkylated to give high diastereo-meric ratios (>94 6) of alkylation products 3 in 60-93% yield16. 

Similar to other tertiary aliphatic amines, quinuclidine easily forms salts with mineral and organic acids, and quaternary derivatives with alkyl halides. However, the rates of reaction of alkyl iodides with quinuclidine are significantly higher than with tertiary aliphatic amines.32 For example, quinuclidine reacts with methyl iodide 50 times faster, and with isopropyl iodide 700 times faster, than does triethylamine. The addition compound of trimethylborane with quinuclidine is more stable than the corresponding adducts of tri-alkylamines. These results can be explained by the almost total... 

---