Sodium allyl derivatives

Formation of AllylEsters. AEyl esters are formed by reaction of aEyl chloride with sodium salts of appropriate acids under conditions of controEed pH. Esters of the lower alkanoic, alkenoic, alkanedioic, cycloalkanoic, benzenecarboxyEc, alkylbenzene carboxyEc, and aromatic dicarboxyEc acids maybe prepared in this manner (25). More information can be found about the reactivity of aEyl compounds (see Allyl alcohol and mono allyl derivatives). 

The synthesis of key intermediate 6 begins with the asymmetric synthesis of the lactol subunit, intermediate 8 (see Scheme 3). Alkylation of the sodium enolate derived from carboximide 21 with allyl iodide furnishes intermediate 26 as a crystalline solid in 82 % yield and in >99 % diastereomeric purity after recrystallization. Guided by transition state allylic strain conformational control elements5d (see Scheme 4), the action of sodium bis(trimethylsilyl)amide on 21 affords chelated (Z)-enolate 25. Chelation of the type illustrated in 25 prevents rotation about the nitrogen-carbon bond and renders... 

Lewis acid induced alkylation of 4-alkoxy-3,5-dialkyl-2-oxazolidinones with allylsilanes gives the 4-allyl derivatives with complete irons stereoselectivity114,115. Cleavage of the oxazolidi-none ring with aqueous sodium hydroxide in ethanol leads to vicinal twP -aminoalkanols. 

While treatment in HBr + AcOH by the Tarbell method424 leads directly from allylphenols 168 to compounds 169, other methods involve the formation of the brominated derivative obtained by adding HBr (in the presence of diphenylamine) to the allylphenol.432 Ring closure is effected by sodium ethoxide. Thus, the ll//-furo[3,2-a]xanthone derivative (177) can be obtained either directly from the allyl derivative (175) or via the bromo derivative (176).432 433 Similarly, 179 has been obtained from the chromone 178.434... 

The first example of Pd-catalyzed enantioselective allylation to be reported was the reaction of l-(l -acetoxyethyl)cyclopentene and the sodium salt of methyl benzenesulfonylacetate in the presence of 10 mol % of a DIOP-Pd complex, which led to the condensation product in 46% ee (Scheme 85) (200). This reaction used a racemic starting material, but the enantioselection was not a result of kinetic resolution of the starting material, because the chemical yield was above 80%. However, in certain cases, the selectivity is controlled at the stage of the initial oxidative addition to a Pd(0) species. In a related reaction, a BINAP-Pd(0) complex exhibits excellent enantioselectivity the chiral efficiency is affected by the nature of the leaving group of the allylic derivatives (Scheme 85) (201). It has been suggested that this asymmetric induction is the result of the chiral Pd catalyst choosing between two reactive conformations of the allylic substrate. 

The difference in acidity of the a-methylene groups in 2-thenyl compared to 3-thenyl derivatives is clearly shown by the reaction of the quaternary ammonium iodides (322) and (323) with sodium amide. While the former yields a cyclopropane, the latter leads to an allyl derivative (Scheme 95) showing that in the case of (323) it is not the a-methylene which is deprotonated (71JOC2236). 

Sodium hydroxide-induced partial allylation was used for preferential reaction at the equatorial OH-4 in l,6-anhydro-2-0-benzyl-P-D-galactopyranose [229]. A similar reaction of allyl 2,6-di-O-benzyl-a-D-galactopyranoside with allyl bromide and sodium hydroxide in benzene at room temperature was not as regioselective, the per-substituted 3,4-di-O-allyl derivative dominated in the reaction product [73]. A high, 87 % yield of the monoallyl derivative was obtained from 1,2 5,6-di-O-isopropylidene-D-mannitol after the treatment with allyl bromide and sodium hydroxide in aqueous acetone [230],... 

Reductive cleavage of 4,6-0-prop-2-enylidene acetals, such as (36), with sodium cyanoborohydride — hydrogen chloride in oxolane gives the corresponding 6-0-allyl derivatives [e.g. (37)] in good yield [242]. The reaction is compatible with the... 

The synthesis of the allyl ethers in nitrogen heterocyclic systems presents an element of complication in that the allylation could occur on the oxygen atom or the basic nitrogen atom. This is a feature of alkylation of ambident anions.3 However, this applies only when the allylation is effected by reacting the oxo or hydroxy derivative of the compound with an allyl halide in the presence of a base.3 The alternative method is to react the appropriate halo derivative with sodium allyloxide in allyl alcohol. The latter approach provides not only better yields of the allyl ethers but also certainty of the constitution of the ethers obtained. A diagnostic tool in deciding between the 1-allyl derivative and the O-allyl compound that has commonly been employed is the infrared absorption of the amide carbonyl in the case of the former which is clearly absent in the latter. 

On the other hand, sodium methoxyalkenyldialkylborates derived from 9-BBN or dicyclohexylborane, undergo stereospecific cross-coupling at —15 °C with allylic halides in the pr ent of cuprous bromide-methyl sulfide to yield stereodefined 1,4-alkadienes (Eq, 94)... 

When 3,3-dimethyl Pd(II) corrole 2.222 was heated to reflux in allyl bromide and then treated with sodium perchlorate, the main product obtained was the C(17)-allyl derivative 2.237 (isolated in 73% yield as the perchlorate salt) (Scheme 2.1.85). The site of addition of the allyl fragment is also the site at which protonation of the... 

It is noteworthy that Takeda and coworkers (Ref. 154) recently proposed allyl isopropenyl dicarbonate made from isopropenyl chloroformate and sodium allyl carbonate as a convenient reagent for the preparation of allyl esters of carboxylic acids. Allyl isopropenyl dicarbonate reacts with carboxylic acids in the presence of DMAP under mild neutral conditions to give allyl esters in high yields. Allyl esters which could be deprotected by palladium catalysts are especially useful in the case of unstable compounds under acid or basic conditions, for example O-glycopeptides, penicillin derivatives, etc. 

Eykman (Ber. 1889, 22, 3172) concluded from an optical examination of a mixture of asarone and safrole that the former is a propenyl and not an allyl derivative, and the constitution of asarone was finally determined by Gattermann and Eggers (Ber. 1899, 32, 289) by synthesizing asarylic aldehyde (ii) from 1 2 4-trimethoxybenzene and then heating this aldehyde with propionic anhydride and sodium propionate, when asarone (iii) was obtained in a yield of 60 per cent. Asarone melts at 62-63° and boils at 296°, specific gravity at 18°, 1.165. 

Appropriate nitro-allyl derivatives for condensation to hexatrienes are usually not easily available, with the exception of nitromethyl-l-cyclohexene and nitro-methyl-l-cycloheptene (34)43. Like nitromethane, 34) does not condense with vinamidinium salts (7) and sodium methoxide, but yields insoluble sodium salts. 

The 8-allyl derivative of 56 can be rearranged to the respective propenyl derivative of 57 by the action of sodium ethoxide (93KGS1545) (Scheme 17). 

Enantioselective allylations of prostereogenic enolates have been attempted using catalytic amounts of a palladium complex incorporating (5,5)-Diop as the chiral ligand. The reactions of ketone zinc enolate 2 with allyl chloride 17 and of the sodium enolate derived from aldehyde 5 with phenyl ether 423 yield 3 and 6 of low enantiomeric excess, respectively. 

Fission of aryl ethers can also be effected by metallic sodium or potassium. For instance, diphenyl ether, which is one of the most resistant ethers, is decomposed by liquid potassium-sodium alloy at room temperature.38 Weber and Sowa have cleaved 4,4 -disubstituted diphenyl ethers into benzene and phenol derivatives by sodium in liquid ammonia.39 Diallyl ether is converted by sodium dust at 35° into allylsodium and sodium allyl oxide, which provides a suitable method for preparation of allylsodium.3 7a Anisole, phenetole, benzyl phenyl ether, and diphenyl ether give the phenols in 90% yield, without by-products, when boiled with sodium or potassium in pyridine.40... 

In addition to allylhalogenomagnesium and allyllithium, the synthesis of allyl coordination compounds of the transition metals may involve allyl derivatives of sodium, zinc, tin, boron, and other main group elements. The synthesis is carried out at 190-295 K in ethers or hydrocarbon solvents. 

Benzoic acid and naphthoic acid are formed by the oxidative carbonylation by use of Pd(OAc)2 in AcOH. t-Bu02H and allyl chloride are used as reoxidants. Addition of phenanthroline gives a favorable effect[360], Furan and thiophene are also carbonylated selectively at the 2-position[361,362]. fndole-3-carboxylic acid is prepared by the carboxylation of 1-acetylindole using Pd(OAc)2 and peroxodisulfate (Na2S208)[362aj. Benzoic acid derivatives are obtained by the reaction of benzene derivatives with sodium palladium mal-onate in refluxing AcOH[363]. 

Formylation of the V-allyl indole derivatives 311 (obtained by allylation of the indole 310) afforded l-allyl-7-formyl-indole 312. Subsequent condensation of 7-formyl indole derivatives 312 with ethyl acetate in presence of sodium ethoxide gave 313 (89S322). Reaction of 312 with N-methylhydroxylamine hydrochloride afforded the cycloadduct, tetracyclic... 

Differences in solubility of the reactants may for example be utilized as follows. Sodium iodide is much more soluble in acetone than are sodium chloride or sodium bromide. Upon treatment of an alkyl chloride or bromide with sodium iodide in acetone, the newly formed sodium chloride or bromide precipitates from the solution and is thus removed from equilibrium. Alkyl iodides can be conveniently prepared in good yields by this route. Alkyl bromides are more reactive as the corresponding chlorides. Of high reactivity are a-halogen ketones, a-halogen carboxylic acids and their derivatives, as well as allyl and benzyl halides. 

The cyclized analog of meralluride is prepared by a similar synthesis. Thus, condensation of camphoric acid (42) (obtained by oxidation of camphor) with ammonia gives the bicyclic succinimide (44). Reaction with allyl isocyanate followed by ring opening and then reaction with mercuric acetate affords the mercury derivative (45) as the acetate rather than the hydroxide as above. Reaction with sodium chloride converts that acetate to the halide (46). Displacement on mercury with the disodium salt of thioglycollic acid affords the diuretic mercaptomerine (47). ... 

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