Diethylmalonate, reaction with

Dicyanocobalamin 870 3,6-Dideoxyhexoses, formation of 747 Dielectric constant 47 Diesenhofer, Johan 84 Diethanolamine, pKa value of 99 Diethylmalonic acid, pKa value of 99 Diethylpyrocarbonate reaction with histidine 126... 

With the less reactive diethylmalonate anion, Gidvani et al. (1932) found only retained products on reaction with the ethyl /8-chloro-crotonates. Carbanions are thus similar to the other anionic nucleophiles. 

The [Co(azasen)]Cl3 semisepulchrate underwent an analogous reaction with diethylmalonate [133] ... 

Continued investigation of MeC(CH2Asl2)3 has led to isolation of two nor-hetero-adamantanes, 28 and 29 (R = COOEt), from reactions with, respectively, diethylmalonate and sodium hydroselenide. As—As distances are 2.469 and 2.483 A respectively, while in the related cyclic triarsine 30 the separation is reduced to 2.42 A . 

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... 

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... 

In 1999, Lavastre and Morken reported a visual colorimetric screen for the detection of effective organometallic catalysts for the allylic alkylation of diethylmalonate. " The colorimetric technique was based upon trapping a 1-naphthol elimination product of the reaction with a diazonium salt (Scheme 4). 

In 1885, Just reported the reaction of sodium diethylmalonate with Af-phenylbenzimino chloride to provide 11. Thermal cyclization provided 12. This work was virtually untouched for several decades, but laid the groundwork for further development. 

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... 

The enantioselective Michael reaction of malonates to nitroolefins catalysed by bifunctional amino-thioureas has recently been reported by Take-moto [161]. Excellent ee (75-93%) were obtained with diethylmalonate after solvent optimisation, toluene being the best solvent both for the activity and for the selectivity. Substituted malonates were then reacted with various nitroolefins under the same conditions. Excellent enantioselectivities were observed (Scheme 45). 

Sulfoximines bearing a chiral sulfur atom have recently emerged as valuable ligands for metal-catalysed asymmetric synthesis.In particular, C2-symmetric bis(sulfoximines), such as those depicted in Scheme 1.51, were applied to the test reaction, achieving enantioselectivities of up to 93% ee. The most selective ligand (R = c-Pent, R = Ph) of the series was also applied to the nucleophilic substitution reaction of l,3-diphenyl-2-propenyl acetate with substituted malonates, such as acetamido-derived diethylmalonate, which provided the corresponding product in 89% yield and 98% ee. 

Another route to the preparation of Cgo derivatives involves the reaction of a halogen derivative of diethylmalonate in the presence of a strong base with fullerenes, which results in a... 

In addition to the two asymmetric syntheses above described, two racemic syntheses of tetraponerines based on the 5=6-5 tricyclic skeleton have been published. Thus, Plehiers et al. [199] have reported a short and practical synthesis of ( )-decahydro-5Tf-dipyrrolo[l,2-a r,2/-c]pyrimidine-5-carbonitrile (238), a pivotal intermediate in the synthesis of racemic tetraponerines-1, -2, -5 and -6, in three steps and 24% overall yield from simple and inexpensive starting materials. The key reaction of the synthesis was a one-pot stereoselective multistep process, whereupon two molecules of A pyrroline react with diethylmalonate to afford the tricyclic lactam ester 239, possessing the 5-6-5 skeleton (Scheme 10). Hydrolysis of the carboethoxy group of 239 followed by decarboxylation yielded lactam 240, that was converted into a-aminonitrile 238 identical in all respects with the pivotal intermediate described by Yue et al. [200] in their tetraponerine synthesis. 

Although most of these early reactions were conducted with allylic acetates, reactions of allylic carbonates, trifluoroacetates, and phosphates also occur. Sodium diethylmalonate also reacts with allylic alcohols in the presence of the iridium-triphenylphosphite catalyst. However, the alcohol itself does not act as a leaving group. Instead, transesterification occurs with one equivalent of malonate nucleophile to form a more labile ester leaving group. 

Substitution of the nine position is a common transformation for acridines. An optimized method for preparing the 9-carboxamides uses BOP/DMF <99SC4341>. Reaction of 9-isothioacridines with the sodium anion of diethylmalonate is followed by alkylation with bromoacetate to afford the spiro[dihydroacridine-9(10i/)-thiazolidines] <99H(51)137>. 

Problem 16.55 Barbiturates are sedative-hypnotic varieties of 5,5-dialkyl substituted barbituric acids. Write the reaction for the formation of Veronal (5,5-diethylbarbituric acid) from the condensation of urea with diethylmalonic ester. [See Problem 17.13(a)]. ... 

Omeprazole is obtained [15] by the reaction of acetyl ethyl propionate 1 with ammonia to give ethyl -3-amino-2,3-dimethyl acrylate 2. Compound 2 was converted to to 2,4-dihydroxy-3,5,6-trimethyl pyridine 3 by treatment with methyl diethylmalonate. Treatment of compound 3 with phosphorous oxychloride produced 2,4-dichloro-3,5/6-trimethyl pyridine 4. 4-Chloro-3/5,6-trimethyl pyridine 5 was obtained by treatment of compound 4 with hydrogen. On treatment of compound 5 with hydrogen peroxide and acetic acid, 4-chloro-3,5,6-trimethyl-pyridine-N-oxide 6 was produced. Treatment of compound 6 with acetic anhydride gave 4-chloro-2-hydroxymethyl-3,5-dimethyl pyridine 7 which was converted to 2-hydroxymethyl-3,5-dimethyl-4-methoxypyridine 8 by treatment with sodium methoxide. Compound 8 was treated with thionyl chloride to produce 2-chloromethyl-3,5-dimethyl-4-methoxypyridinc 9. Compound 9 interacts with 5-methoxy-2-mercaptobenzimidazole to give 5-methoxy 2-[((4-methoxy-3,5-dimethyl-2-pyridinyl)methyl)thio]-lH-bcnzimidazole 10 which is oxidized to omeprazole 11. 

The effect of several chiral ligands on the Sn reaction of l-(2-naphthyl)ethyl acetate and its 6-methoxy-substituted analogue with diethylmalonate anion were investigated.97 The best results (90% ee) were obtained using a Pd-bis(dibenzylidene)ace- tone/(R,R)-i-Pr-DUPHOS (22) catalyst in DMSO at 70 °C. However, the substitution elimination ratio was only 15 85. 

Similarly, reaction of diethylmalonate with olefins in the presence of a mixture of Cu(II) acetate and Mn(III) or Co(III) acetate provides a convenient route to 7,5-unsaturated acids or to 7-lactones226a,b ... 

In the photostimulated reaction of Phi with the monoanion of acetylacetone or with the diethylmalonate anion, no substitution products were found. On the other hand, in the reaction of anthrone anion (29) with Phi a 95% yield of the substitution product (126) was formed (equation 86)169. 

The reaction of the tetrafluoroethylene trimer with one equivalent of diethylmalonate and two equivalents of sodium hydride in dry ether gives a mixture of 5-carboethoxy-6-ethoxy-2,3,4-tris(trifluoromethyl)-2-pyran and 5-carboethoxy-6-ethoxy-2,3,4-tris(trifluoromethyl)-4-pyran in a 2.1 1 ratio with a total yield of 71% (98JFC(88)169). 

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