Diphenyl malonate

We found that cyclic benzeneboronic anhydride (BBA), diphenyl carbonate (DPC) (4), diphenyl terephthalate (DPT) (5), diphenyl oxalate (DPO) (5), diphenyl malonate (DPM) (5), tetraphenyl orthocarbonate (POC) (6), hexaphenyl orthoterephthalate (POT) (7) are suitable compounds as chain extenders. 

Table III shows analytical values of the polymer prepared. The presence of a small amount of terminal acetyl group was found with diphenyl malonate and small amounts of terminal formyl groups with phenyl triphenoxyacetate and diphenyl oxalate. A trace of phenol...

Diphenyl Malonate and Diphenyl Oxalate. Above 200°C, the half ester of malonic acid decomposes to carbon dioxide and an ester of acetic acid, and the half ester of oxalic acid decomposes to carbon dioxide and an ester of formic acid. Diphenyl malonate and diphenyl oxalate are chain extenders that decrease the terminal PET COOH content by these decomposition reactions. 

The mechanism with diphenyl malonate is indicated by Reactions... 

In contrast to other acids, anhydrous hydrogen fluoride does not cause hydroly SIS and decarboxylation of the malonic acid residues in these reactions [5]. It is a good reagent for the cyclization of a-benzamidoacetophenones to 2,5 diphenyl-oxazoles [6] (equation 7) The same reaction with concentrated sulfuric acid gives cyclic product with only a 12% yield [6]... 

A round-bottomed flask containing diphenyl ether (14 mL) was placed in an oil bath which was heated to 250 °C and malonate 132 (12 mmol) was added slowly. The mixture was kept under reflux for 1 h. During this time vapors evolved and a white solid formed. The solid was filtered and washed with hexane to remove excess Ph20. This provided quinoline ethyl ester 133 as a white solid in 80% yield. For quinoline 133 mp = 238-239 °C IR (KBr) 1698 (ester) cm. ... 

A mixture of 48 parts by weight of diethyl[(3,4-methylenedioxyanilino)methylene] malonate and 500 parts by weight of diphenyl ether is refluxed for 1 hour. The mixture is allowed to cool to about 25°C with stirring and 500 parts by weight of petroleum ether are added. Filtration gives 3-carbethoxy-6,7-methylenedioxy-4-hydroxy-quinoline as a brown solid, MP 276° to 281°C. Several recrystallizations from dimethylformamide gives almost colorless analytical material, MP 285° to 286°C, (decomposes). 

The starting material may be produced by reacting 6-amino-2-methylthiopyrimidine with ethoxymethylene malonic acid diethyl ester. The intermediate thus produced is converted by boiling in diphenyl ether to 6-ethoxycarbonyl-2-methylthio-5-oxo-5,B-dihydropyrido-[2,3-d]pyrimidine. That is hydrolyzed by sodium hydroxide to cleave the ethoxy group and then ethylated with diethyl sulfate to give the starting material. 

Chiral phosphinous amides have been found to act as catalysts in enantio-selective allylic alkylation. Horoi has reported that the palladium-catalyzed reaction of ( )-l,3-diphenyl-2-propenyl acetate with the sodium enolate of dimethyl malonate in the presence of [PdCl(7i-allyl)]2 and the chiral ligands 45 gave 46 in 51-94% yields and up to 97% ee (Scheme 38). It is notorious that when the reaction is carried out with the chiral phosphinous amide (S)-45a, the product is also of (S) configuration, whereas by using (R)-45b the enantiomeric (R) product is obtained [165]. 

Another more specific characteristic can allowed the differentiation between homogeneous and colloidal catalysts. In Pd-catalysed allylic alkylation rac-3-acetoxy-1,3-diphenyl-l-propene with dimethyl malonate, homogeneous and colloid species reacts at different rates with both substrate enantiomers, obtaining in the case of Pd colloids an excellent kinetic resolution (see Section 4) [44]. 

Scheme 1. Asymmetric allylic alkylation of rac-3-acetoxy-l,3-diphenyl-l-propene (rac-I) with dimethyl malonate catalysed by Pd/1 colloidal system. (Reprinted from Reference [44], 2004, with permission from American Chemical Society.)...

Catalytic reaction conditions [Pd/l]j.oii (ca. 2.35 x 10 mmols) and 1 (5.8 X 10 mmols) was dissolved in 2cm of CH2CI2. roc-1,3-diphenyl-2-propenyl acetate (252mg, 1 mmol), dissolved in 7 cm of CH2CI2, was added, followed by dimethyl malonate (396mg, 3mmols), BSA (610mg, 3 mmols), and a catalytic amoimt of KOAc. After each 24 h, 1 mmol of roc-I was added. 

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. 

Condensation of aminopyrazole 116 with ethoxy-methylene malonic ester gives the product of addition-elimination (117), which is then cyclized to the piperidone by heating in diphenyl ether. The product tautomerizes spontaneously to the hydroxypyridine 118. The hydroxyl group is then converted to the chloro derivative by means of phosphorus oxychloride (119). Displacement of halogen by n-butylamine gives... 

Methyl-37/-indoles react with 2 equiv of diethyl malonate in hot diphenyl ether to give pyranoindolizines such as 125. However, under the same conditions, 2-methvl-2.3-di hydro-1 //-indoles give the regioisomeric pyrrolopyrano-quinolines, for example, 126 (Scheme 35) <2003JHC297>. 

Honciuc A, Jaiswal A, Gong A, Ashworth K, Spangler CW, Peterson IR, Dalton LR, Metzger RM (2005) Current rectification in a Langmuir-Schaefer monolayer of fullerene-bis-[4-diphenylamino-4 -(N-ethyl-N-2 -ethyl)amino-l,4-diphenyl-l,3-butadiene] malonate between Au electrodes. J Phys Chem B109 857-871... 

The reactions of isopropylidene (l-methylthioalkylidene)malonates and arylamines in boiling ethanol for 2-4 hr, or in diphenyl ether at 140°C for 0.5 hr, afforded isopropylidene l-(aryIamino)alkylidenemalonates (440) in 54-87% yields (87S482). 

The cyclization of diethyl /V-[2-(l-pyrrolyl)phenyl]aminomethylene-malonate by heating in diphenyl ether for 8 min gave 8-pyrrolylquinoline-3-carboxylate (570) in 23% yield, while its reaction in boiling phosphoryl chloride for 15 min afforded the tricyclic pyrroloquinoxaline (571) in 76% yield [75JCS(P1)2409). 

It was later claimed that the thermal cyclization of bis(aminomethylene-malonates) (601, R = H, Me, Cl, N02, R1 = Et) by heating in refluxing diphenyl ether for 15-30 min under nitrogen afforded 8-(substituted amino)quinoline-3-carboxylates (603) in 31-75% yields (78USP4123536). In the cases of the methyl and chloro derivatives (601, R = Me, Cl, R1 = Et), l,10-phenanthroline-3,8-dicarboxylates (602, R = Me, Cl, R1 = Et) could also be isolated as byproducts in 3-4% yields. 

The cyclization of diethyl A[-(4-methylcinnolin-8-yl)aminomethylene-malonate in diphenyl ether at 245°C for 20 min gave pyrido[3,2-/i]cinnoline-8-carboxylate (610) in 31% yield (51JOC1414). 

The thermal ring closure of diethyl /V-(3-aminophenyl)aminomethylene-malonate (757 R = NH2, R1 = H) and its 4-fluoro derivative (757, R = NH2, R1 = F) in boiling diphenyl ether in the presence of acetic anhydride gave the corresponding ethyl 7-acetamido-4-hydroxyquinoline-... 

From a study of the thermal ring closure of 2-pyridylaminomethylene-malonates (1001) by heating in diphenyl ether, Lappin found that pyri-do[l,2-a]pyrimidine-3-carboxylates (1002) were formed from those malo-... 

Cyclization of diethyl N-(5-aminocarbonyl-2-pyridyl)aminomethylene-malonate (1001, R = H, R1 = 5-CONH2) in refluxing diphenyl ether for 2 hr gave 1,8-naphthyridine (1003, R = H, R1 = 6-CONH2) in 48% yield (72JMC1203). Later, it was proved that the product was a pyrido[l,2-u]pyrimidine (1002, R = H, R1 = 7-CONH,) [77JCS(P 1)789]. 

Sardesai and Sunthankar studied the cyclization of diethyl )V-(2-amino-phenyl)aminomethylenemalonate (162, R = H) (57MI2 59MI1). No cyclization occurred in refluxing xylene in the presence or absence of a catalyst (p-toluenesulfonic acid or sodium hydroxide), or in acetic anhydride, or in a mixture of acetic anhydride and concentrated sulfuric acid. Benzimidazole and benzimidazolone were obtained in 20% and 66% yields, respectively, when 162 (R = H) was distilled in vacuo. Benzimidazolone was the product when 162 (R = H) was heated in boiling diphenyl ether, o-Phenylenediamine was reacted with diethyl acetylmalonate at 140°C for 4 hr to give 2-methylbenzimidazole and diethyl malonate (85S555). 

Sulfinpyrazone Sulfinpyrazone, l,2-diphenyl-4,2-(phenylsulfinil)ethyl-3,5-pyrazolidine-dione (3.2.8), is an analog of phenylbutazone that is synthesized in the analogous manner of condensing hydrazobenzol with 2-(2-phenyltioethyl)malonic ester into pyrazolidinedione (3.2.7), and the subsequent oxidation of thiol ether by hydrogen peroxide in acetic acid into the sulfoxide, sulfinpyrazone (3.2.8) [70,71]. 

The presented protocol tolerated a spectrum of enolizable species including dialkyl malonates, 1,3-diketone, ketoester, 1,3-dinitriles, and nitroesters to be added to the model trons-chalcone 1,3-diphenyl-propenone producing the desired Michael adducts in good to excellent yields (67-99%) and with attractive ee values (88-93%). Figure 6.41 shows some selected results of the nucleophile evaluation. 

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