BUTYL Malonate

DI-ferf-BUTYL MALONATE (Malonic add, di-ferf-butyl ester) 

Di-tert-butyl malonate. A 1-1. three-necked flask is fitted with a thermometer, a mercury- or rubber sleeve-sealed mechanical stirrer, a reflux condenser protected by a calcium chloride guard tube, and a dropping funnel (either pressure-equalized or protected by a calcium chloride guard tube). A mixture of 100 ml. (about 1 mole) of ter/-butyl alcohol, dried by distillation from sodium,2 and 80 ml. (0.63 mole) of dry dimethylanilinc (Note 5) is placed in the flask, the stirrer is started, and a solu- 

Better results are obtained by using a flat-bottomed flask, which permits the insoluble malonic acid to be distributed over a greater surface. 

The reaction mixture is heterogeneous at first, and if the acid is not finely powdered, some of it remains unreacted. Attempts to carry out the reaction on a larger scale resulted in some charring and lower yields. 

Eastman Kodak Company white-label quality thionyl chloride is satisfactory. 

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In the alkylation of l-phenylpyrazole-3,5-diones both carbon and oxygen compete successfully with nitrogen (B-76MI40402). Phenylbutazone (Section 4.04.4.1.1) can be prepared by reaction of l,2-diphenylpyrazole-3,5-dione with -butyl halides and alkali, even if the industrial procedure uses -butyl malonic diesters and hydrazobenzene (Section 4.04.3.1.2(h)). 

Dicyclohexylcarbodiimide n-Butyl Malonic Acid Ethyl Ester Hydra 2oben2ene... 

The separate extracts are made acid to Congo paper with concentrated HOI, extracted with ethyl acetate, the extracts are washed neutral with a little water, dried and concentrated under vacuum. The colorless oil which remains is recrystallized twice from ether/petroleum ether, whereupon n-butyl malonic acid-N,N -diphenylhydrazide is obtained in the form of short needles which melt at 116°-118°C. 

A gas ehromatographic analysis on the produet by the submitter, using an 0.3 x 80 cm. column packed with 10% silicone rubber (SE-30) supported on acid-washed, 60-80 mesh Chromasorb P at 80°, exhibited a single peak. The retention times of di-ter(-butyl malonate, di-fert-butyl diazomalonate, and p-toluenesulfonyl azide were 2, 6, and 9 minutes, respectively. The purity of the product obtained by the checkers was estimated from proton magnetic resonance spectra to be ca. 94%, the remainder being di-tert-butyl malonate. 

The diazo transfer reaction between p-toluenesulfonyl azide and active methylene compounds is a useful synthetic method for the preparation of a-diazo carbonyl compounds. However, the reaction of di-tert-butyl malonate and p-toluenesulfonyl azide to form di-tert-butyl diazomalonate proceeded to the extent of only 47% after 4 weeks with the usual procedure." The present procedure, which utilizes a two-phase medium and methyltri-n-octylammonium chloride (Aliquat 336) as phase-transfer catalyst, effects this same diazo transfer in 2 hours and has the additional advantage of avoiding the use of anhydrous solvents. This procedure has been employed for the preparation of diazoacetoacetates, diazoacetates, and diazomalonates (Table I). Ethyl and ten-butyl acetoacetate are converted to the corresponding a-diazoacetoacetates with saturated sodium carbonate as the aqueous phase. When aqueous sodium hydroxide is used with the acetoace-tates, the initially formed a-diazoacetoacetates undergo deacylation to the diazoacetates. Methyl esters are not suitable substrates, since they are too easily saponified under these conditions. 

Di-terf-butyl malonate, 59, 66 Di-tert-butyl peroxide, 55, 61... 

Di-terf-butyl malonate is available commercially either directly from Fluka AG, Buchs, Switzerland, or from its North American representative, Tridom Chemical Inc. Alternatively this compound may be prepared from malonic acid. ... 

Di-(ert-butyl malonate Malonic acid, di-terf-butyl ester (8) Pro-panedioic acid, bis(l,l-dimethylethyl)ester (9) (541-16-2) p-ToIuenesulfonyl azide (8) Benzenesulfonyl azide, 4-methyl- (9) (941-55-9)... 

In the presence of zinc chloride, stereoselective aldol reactions can be carried out. The aldol reaction with the lithium enolate of /-butyl malonate and various a-alkoxy aldehydes gave anti-l,2-diols in high yields, and 2-trityloxypropanal yielded the syn-l,2-diol under the same conditions.633 Stoichiometric amounts of zinc chloride contribute to the formation of aminoni-tropyridines by direct amination of nitropyridines with methoxyamine under basic conditions.634 Zinc chloride can also be used as a radical initiator.635... 

Di-fer -butyl malonate has been prepared by the reaction of malonyl dichloride and fer/-butyl alcohol in the presence of a base,8,11 and of malonic acid with isobutylene in the presence of sulfuric acid.3 The present procedure was based on the former method and developed from studies initiated by P. C. Mukharji of the University College of Science and Technology, Calcutta. 

ETHYL ferf-BUTYL MALONATE (Malonic acid, ethyl [Pg.18]

Ethyl tert-butyl malonate has been prepared by adding tert-butyl acetate and ethyl carbonate to sodium triphenylmethyl,3 and from ethyl malonyl chloride and fer/-butyl alcohol.4 The present procedure is an adaptation of that for the preparation of di-fer(-butyl malonate.2... 

For convenience, the reaction was carried out overnight. The reaction time may probably be shortened (compare the preparation of di-/er/-butyl malonate 2 3 4 5). 

The tri-(/erf-butyl) ester (511) was prepared in 40% yield when the thiolactam (510) was first treated with di-rm-butyl malonate and DBU and then with triphenylhosphine and DBU in boiling toluene (85CC583). 

A similar reaction was carried out with 3a-iodo-5a-androstan-2/3-yl isothiocyanate and di-(7er/-butyl) malonate to give (andost-2-eno[2,3-[Pg.132]

The lithium enolate of di-i-butyl malonate undergoes a stereoselective aldol reaction with Qf-alkoxyaldehydes to give anft-l,2-diol derivatives in the case of the highly hindered 2-trityloxypropanal, the stereochemistry is reversed. 

Thiopentone. (Pentothal, Intraval.) 34 g of clean metallic sodium are dissolved in 1 liter of dry ethanol. To this solution add 130 g of ethyl-1-methyl butyl malonic ester. This mixture is stirred, 60 g of powdered thiourea is added and the whole is refluxed for 10 hours. Remove the alcohol by distilling under reduced pressure, dissolve the residue with water and acidify with hydrochloric... 

Ice-acetone bath. The bottle is closed with a rubber stopper which is clamped or wired securely in place (Note 3) and is shaken mechanically at room temperature until the suspended malonic acid dissolves (Note 4). The bottle is chilled in an ice-salt bath and opened then the contents are poured into a separatory funnel containing 250 ml. of water, 70 g. of sodium hydroxide, and 250 g. of ice. The mixture is shaken (carefully at first), the layers are separated, and the aqueous portion is extracted with two 75-ml. portions of ether. The organic layers are combined, dried over anhydrous potassium carbonate, and filtered into a dropping funnel attached to the neck of a 125-ml. modified Claisen flask (Note 5). The flask is immersed in an oil bath at about 100°, and the excess isobutylene and ether are removed by flash distillation effected by allowing the solution to run in slowly from the dropping funnel. The dropping funnel is then removed, and the residue is distilled at reduced pressure. The fraction boiling at 112—115°/31 mm. is collected. The yield of colorless di-tert-butyl malonate is 60.0 62.0 g. (58-60%), 1.4158-1.4161,... 

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