Diethyl diethylmalonate

Barbiturates are prepared by treating a derivative of diethyl malonate with urea in the presence of sodium ethoxide as a catalyst. Following is an equation for the preparation of barbital, a long-duration hypnotic and sedative, from diethyl diethylmalonate and urea. 

Barbituric acid and 2-thiobarbituric acid are readily prepared by the condensation of diethylmalonate with urea and thiourea respectively, in the presence of sodium ethoxide. The use of substituted derivatives of urea and thiourea and of diethyl malonate will clearly lead to a wide range of barbituric and thiobarbituric acids having substituents in the i, 3, or 5 positions. 

Reaction of 2-aminopyridine with dimethyl 2-methylmalonate in the presence of some drops of cone. HCl at 150°C for 1 h (96EUP733633), and with diethyl 2-(l-decyl)malonate at 120°C for 5 min (94JCR(S)206) gave 2-hydroxy-3-methyl- and 2-hydroxy-3-(l-decyl)-4//-pyrido[l, 2-n]pyrimidin-4-ones in 2.2% and 7.5% yields, respectively. Reaction of 3-benzyl-2-aminopyridine and diethylmalonate at 190-200 °C for 4 h yielded 9-benzyl-2-hydroxy-4//-pyrido[l, 2-n]pyrimidin-4-one (01MIP9). Cyclocondensation... 

Diethylmalonate anion does not apparently react cleanly with dioxygen and in this case a complex mixture of products of self-condensation is obtained. However substituted diethylmalonates are usefully converted into hydroxylated products. In the case of diethyl phenylmalonate conversion into the corresponding carbonyl compound, ethyl phenylglyoxalate, was observed — presumably according to the mechanism given in Scheme 19. 

A sub case in this category is the benzylation of enolates through the Srn 1 process. In this way, both a-nitro- and a-chloro-4-nitrocumene are alkylated by the enolates of 2-nitropropane, diethylmalonate, or diethyl 2-butylmalonate. A particular case of benzylic C-C fragmentation is the electron transfer photosensitized Cope rearrangement of 2,5-diphenyl-1,5-hexadienes [218,219]. 

Previously cyclopropane-1,1-dicarboxylic acid had been prepared2-4 by hydrolysis of the corresponding diester. The preparation of 1,1-dicarboalkoxycyclopropanes by a conventional double alkylation of diethyl malonate with 1,2-dibromoethane was severely complicated by the recovery of unreacted diethylmalonate. This required a rather difficult distillation to separate starting material and product. In fact, many commercially offered lots of cyclopropane diester contain extensive amounts of diethyl malonate. Furthermore, preparation of the diacid required a separate and relatively slow saponification of the diester.5... 

The synthesis of 10-oxa-l 1-deoxyprostanoids that is of prostanoids with a 7-lactone structure has been reported in the patent literature82 and from a research group from the Research Triangle Institute83. The latter synthesis started with diethyl-2-(3-cyclooctenyl)-malonate 112 which can be prepared according to the literature M, 85) jjy a treating the sodium salt of diethylmalonate with 3-bromocyclooctene or 1,2-dibromocyclooctane. 

The 1,3-bisamide 5.7-(m)-dioxo-cyclam (47) is prepared by reaction of 2,3,2-tet with a bisacy-lating reagent, commonly diethylmalonate, and the 1,2-bisamide 2,3-dioxo-cyclam (50) is similarly prepared from 3,2,3-tet by reaction with diethyl oxalate (Scheme 14).54 The (5,12)-(/ra ,y)-dioxo-cyclam (51) is prepared by a 2 + 2 condensation of en with (m)ethylacrylate.55... 

Derivation By the interaction of diethyl ester or diethylmalonic acid and urea. 

Sodium hydride (60% oil dispersion, 0.15 g, 0.38 mmol) was washed with hexane (2x2 mL) and THF (1x2 mL). Note exercise great care with NaH, particularly after the hexane wash the NaH should be kept under nitrogen or argon.) To a suspension of oil-free sodium hydride in THF (5mL) was added diethylmalonate (0.770 mL, 0.38 mmol). After 15 min of stirring, the resulting diethyl malonate anion solution was added via a cannula to a solution of the allylic benzoate (131 mg, 0.56 mmol), Pd(PPh3)4 (45 mg, 0.039 mmol), and triphenylphosphine (100 mg. 

Finally, sodium <%-(phenylamino)-with elimination of the sulfonate group 864... 

Sodio diethylmalonate is an example of type (a). Reaction with fluoroben-zene-Cr(CO)3 proceeds to completion after 20 h at 50 °C in HMPA to give the diethyl phenylmalonate complex in over 95% yield [2]. There is no evidence for an... 

A mole each of diethyl fnmarate and diethylmalonate reacts together in the presence of freshly prepared sodium ethoxide to result into the formation of ethylpropane-1, 1, 2, 3-tetracarboxylate. In fact, diethylmalonate gets split up as shown above by the dotted line, the double bond in diethyl fnmarate changes into a single covalent bond thereby the residual,... 

To a 75 mL solution of NaOEt in absolute ethanol prepared by addition of 4.5 g sodium in absolute ethanol were added 9.0 g benzamidine hydrochloride and 10 g carefully purified methyl a,a-diethylmalonate. The mixture was heated for 5 h at 70°C. The alcohol was partially removed by a current of dry air, and the residue was acidified with a slight excess of cone. HCl. After removal of the precipitated NaCl, the solution was further concentrated on the steam bath. The addition of water caused 5,5-diethyl-2-phenyl-4,6-diketo-tetrahydro-pyrimidine to separate in white needles, in an amount of 3.0 g. The product was further purified by recrystallization from dilute acetic acid. 

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