Lithium diethylamine

Eremophilane sesquiterpenes are not widely distributed in Eremophila species. In fact, the only other example so far known is the aldehyde (70) which occurs in E. rotundifolia (66). The structure of 70 was deduced largely from H- and C-nmr spectral data and, the absolute, stereochemistry by correlation with eremophilone. The keto aldehyde was reduced with sodium borohydride-cerium trichloride to give a mixture of diastereomeric diols. The major compound was assigned the 9a-configuration. The derived diacetate, on treatment with lithium-diethylamine, gave mainly the 9-allylic alcohol which was oxidised to eremophilone with Collin s reagent. 

When butyllithium is used as a base it abstracts a proton in this case a proton attached to nitrogen The source of lithium diethylamide must be diethylamine... 

Whilst some organic compounds can be investigated in aqueous solution, it is frequently necessary to add an organic solvent to improve the solubility suitable water-miscible solvents include ethanol, methanol, ethane-1,2-diol, dioxan, acetonitrile and acetic (ethanoic) acid. In some cases a purely organic solvent must be used and anhydrous materials such as acetic acid, formamide and diethylamine have been employed suitable supporting electrolytes in these solvents include lithium perchlorate and tetra-alkylammonium salts R4NX (R = ethyl or butyl X = iodide or perchlorate). 

Chlorotris(diethylamino)titanium24 is prepared directly from diethylamine, lithium and tilani-um(IV) chloride in the presence of styrene as reducing agent25. However, a metathesis reaction between tetrakis(diethylamino)titanium26 28 and titanium(lV) chloride gives a cleaner product and is thus preferred. Bromotris(diethylamino)titanium is prepared similarly7,29. 

Orders for certain chemicals used to make psychedelics (especially large orders in suspect areas) are sometimes checked by narcs. Indole, lithium aluminum hydride, trimethoxybenzaldehyde, phenyl-2-propanol, diethylamine, olivetol and ergotamine are among those watched. The vast majority of the homologs and analogs described here are, however, legal to manufacture and use. 

Reactions of amines with alkenes have been reviewed298,299. Alkali metal amides are active homogeneous catalysts for the amination of olefins. Thus diethylamine and ethylene yield triethylamine when heated at 70-90 °C at 6-10 atm in the presence of lithium diethylamide and /V./V./V. /V -tetrarncthylcthylcncdiaminc. Solutions of caesium amide promote the addition of ammonia to ethylene at 100 °C and 110 atm to give mixtures of mono-, di- and triethylamines300. The iridium(I)-catalysed addition of aniline to norbomene affords the anilinonorbomane 274301. Treatment of norbomene with aniline... 

Better reagents than lithium aluminum hydride alone are its alkoxy derivatives, especially di- and triethoxyaluminohydrides prepared in situ from lithium aluminum hydride and ethanol in ethereal solutions. The best of all, lithium triethoxyaluminohydride, gave higher yields than its trimethoxy and tris(/er/-butoxy) analogs. When an equimolar quantity of this reagent was added to an ethereal solution of a tertiary amide derived from dimethylamine, diethylamine, W-methylaniline, piperidine, pyrrolidine, aziridine or pyrrole, and the mixture was allowed to react at 0° for 1-1.5 hours aldehydes were isolated in 46-92% yields [95,1107], The reaction proved unsuccessful for the preparation of crotonaldehyde and cinnamaldehyde from the corresponding dimethyl amides [95]. 

In addition to previously described syntheses4-5 by diazo group transfer with deformylation,6 2-diazocyclohexanone has been prepared by two variants of this method. In one, the reaction of 2-(hydroxymethylene)cyclohexanone with -toluene-sulfonyl azide is carried out in ether/diethylamine, and an enamine is assumed to be formed as an intermediate 7 in the other, the sodium salt of the hydroxymethylene compound was treated with the lithium salt of p-carboxybenzenesulfonyl azide... 

This important synthetic problem has been satisfactorily solved with the introduction of lithium dialkylamide bases. Lithium diisopropylamide (LDA, Creger s base ) has already been mentioned for the a-alkylation of acids by means of their dianions1. This method has been further improved through the use of hexamethylphosphoric triamide (HMPA)2 and then extended to the a-alkylation of esters3. Generally, LDA became the most widely used base for the preparation of lactone enolates. In some cases lithium amides of other secondary amines like cyclo-hexylisopropylamine, diethylamine or hexamethyldisilazane have been used. The sodium or potassium salts of the latter have also been used but only as exceptions (vide infra). Other methods for the preparation of y-Iactone enolates. e.g., in a tetrahydrofuran solution of potassium, containing K anions and K+ cations complexed by 18-crown-6, and their alkylation have been successfully demonstrated (yields 80 95 %)4 but they probably cannot compete with the simplicity and proven reliability of the lithium amide method. 

Hohe Ausbeuten an N,N-Dialkyl-anilinen, z.B. N,N-Dieihyl-anilin (87%) erhalt man bei der Umsetzung von Brombenzol mit Diethylamin unter Verwendung von Lithium-... 

Auch die Alkalimetalle selbst konnen als Katalysator eingesetzt werden8,9 (s.a. oben Herstellung von l-Ethyl-piperidin) sie bilden mit dem Amin das katalytisch wirksame Alkalimetall-amid. So hat sich fur die Addition von Diethylamin an 4-Ethenyl-4-methyl-benzol zu l-(2-Diethylamino-ethyl)-4-methyl-benzol die Verwendung von Lithium (14mol%) als geeignet erwiesen8. 

C, Preparation of the 1 1 Adduct of Lithium Diethylamide and Butadiene. Butadiene (4.9 g, 9.07 mmole) was dissolved in 400 ml of purified diethylamine. ji-Butyllithium (9% mmole) in hexane was added dropwise over a period of one hour at 0°C. 

In order to verify this hypothesis, we have isolated a mixture of l-diethylamino-2-butene in 65-70% of yield by the reaction of equimolar amounts of lithium diethylamide and butadiene in diethylamine. This product consists of a mixture of the cis and trans olefins in a ratio of 1 to 2. In addition, we have also observed about 5% of l-diethylamino-3-butene by... 

The lithium salt of A/-ethy)ethanamine (diethylamine) is called lithium diethylamide,4 but this nomenclature can lead to confusion With compounds of the type RC02NH2, which are derived from carboxylic acids and also are... 

Although various transition-metal complexes have reportedly been active catalysts for the migration of inner double bonds to terminal ones in functionalized allylic systems (Eq. 3.2) [5], prochiral allylic compounds with a multisubstituted olefin (Rl, R2 H in eq 2) are not always susceptible to catalysis or they show only a low reactivity [Id]. Choosing allylamines 1 and 2 as the substrates for enantioselective isomerization has its merits (1) optically pure citronellal, which is an important starting material for optically active terpenoids such as (-)-menthol, cannot be obtained directly from natural sources [6], and (2) both ( )-allylamine 1 and (Z)-allylamine 2 can be prepared in reasonable yields from myrcene or isoprene, respectively, The ( )-allylamine 1 is obtained from the reaction of myrcene and diethylamine in the presence of lithium diethylamide under Ar in an almost quantitative yield (Eq. 3.3) [7], The (Z)-allylamine 2 can also be prepared with high selectivity (-90%) by Li-catalyzed telomerization of isoprene using diethylamine as a telomer (Eq. 3.4) [8], Thus, natural or petroleum resources can be selected. 

In 1973, Tsuruta and his coworkers79) established that diethylamine adds stoichio-metrically to styrene in the presence of some lithium diethylamide. The reaction mechanism involves two steps namely a kind of anionic initiation and subsequent proton transfer, due to the difference in the acidity between the benzylic and amine substrate ... 

As shown, this problem could be circumvented in one case by using trimethylstannyl diethylamine (30) but the sequence given is obviously impractical. As shown in the Section 5.3 stannylated ynamines are most conveniently prepared from aminoethyhyl lithium and triorganostannyl halides. 

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