Synthesis of 3,5-diaryl-4-chlorophthalates by [4+2] cycloaddition of 1-ethoxy-2-chloro-1,3-bis(trimethylsilyloxy)-1,3-diene with dimethyl acetylenedicarboxylate and subsequent site-selective Suzuki-Miyaura reactions

The [4+2] cycloaddition of 1-ethoxy-2-chloro-1,3-bis(trimethylsilyloxy)-1,3-diene with dimethyl acetylenedicarboxylate (DMAD) afforded dimethyl 4-chloro-3,5-dihydroxyphthalate. Site-selective Suzuki-Miyaura reactions of its bis(triflate) provide a convenient approach to 3,5-diaryl-4-chlorophthalates containing two different aryl groups.     

Reaction of Dimethyl Acetylene-Dicarobxylate With Triazinone

Abstract

The addition of dimethyl acetylenedicarboxylate (DMAD) to 6-menthy-1, 2,4-triazlne-3(2H)thione-5(4H)-one afforded 2-methoxylcarboxy-7-methyl-1,3-thiazino[3,2-b][1,2,4]triazine-4,8-dione.     

A new selective preparation of ethyl 7-aminopteridine-6- carboxylate derivatives and related compound

A series of ethyl 7-amino-2,4-dioxopteridine-6-carboxylates 4 and ethyl 7-amino-4-oxo-2-thioxopteridine-6-carboxylates 5 , of interest biologically, has been prepared in one step from the reaction of such vicinal-diamines as 1,3-dialkyl-5,6-diaminouracils 2 or 1,3-dialkyl-5,6-diamino-2-thiouracils 3 with diethyl (E)-2,3-dicyanobutenedioate ( 1 ). Moreover, ethyl 3-amino[1,2,4]triazino[2,3-a]-1H-benzimidazole-2-carboxylate ( 11 ) was also obtained from the reaction between 1,2-diamino-1H-benzimidazole ( 10 ) and 1 . The structural studies of 4, 5 , and 11 prepared were carried out by nmr experiments in some details.     

Synthesis and photolysis of N-phthalimidoaziridines with electron-withdrawing substituents

Mono-, bi-, tetra-, and pentacyclic N-phthalimidoaziridines with electron-withdrawing substituents in the three-membered ring have been obtained by the oxidative addition of N-aminophthalimide to dimethyl fumarate, ethyl cinnamate, N-phenyl-and N-benzylmaleimide, and endotricyclo[6.2.1.0^2,7]undeca-4,9-diene-3,6-dione. Photolysis of 3-benzyl-6-phthalimido-3,6-diazabicyclo-[3.1.0]hexane-2,4-dione obtained in this way in the presence of dimethyl acetylenedicarboxylic acid (DMAD) gives in low yield the dimethyl ester of 3-benzyl-2,4-dioxo-8-phthalimido-3,8-diazabicyclo[3.2.1]oct-6-ene-6,7-dicarboxylic acid, the product of 1,3-dipolar cycloaddition to the N-phthalimidoazomethinylide formed as intermediate. However photolysis of this phthalimidoaziridine in the presence of other 1,3-dipolarophiles, like photolysis in the presence of DMAD of the remaining phalimidoaziridines, does not lead to a 1,3-dipolar cycloaddition product. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1320–1328, September, 2006.     

Direct heterocyclization of tetrahydroisoquinolin-1-ylideneacetic acids by the action of 5-arylfuran-2,3-diones

Aroylketenes generated in situ by thermolysis of 6-aryl-2,2-dimethyl-4H-1,3-dioxin-4-ones reacted with 3,3-dialkyl-1-methyl-3,4-dihydroisoquinolines to give (1Z,3Z)-4-aryl-4-hydroxy-1-[3,3-dialkyl-3,4-dihydroisoquinolin-1(2H)-ylidene]but-3-en-4-ones. The crystalline and molecular structure of (1Z,3Z)-4-hydroxy-1-[6,7-dimethoxy-3,3-dimethyl-3,4-dihydroisoquinolin-1(2H)-ylidene]-4-phenylbut-3-en-2-one was studied by X-ray diffraction.     

α-Thioureidoalkylation of 4-alkyl- and 4-phenylthiosemicarbazides

Previously unknown 1,3-dialkyl-4,5-bis[4-alkyl(phenyl)thiosemicarbazido]imidazolidine-2-thiones and 4,5,7-trialkylperhydroimidazo[4,5-e]-1,2,4-triazine-3,6-dithiones have been synthesized by the α-thio-ureidoalkylation of 4-alkyl(phenyl)thiosemicarbazides using 1,3-dialkyl-4,5-dihydroxyimidazolidine-2-thiones.     

Synthesis of dimethyl 1,2-dihydroisoquinolines through the reaction of isoquinoline and dimethyl acetylenedicarboxylate in the presence of amides

Isoquinoline reacts smoothly with dimethyl acetylenedicarboxylate (DMAD) in the presence of amides to produce dimethyl 2-[1-[aryl(alkyl)carbonylamino]-2(1H)-isoquinolinyl]-2-butenedioates. Reaction of quinoline with DMAD in the presence of benzamide led to dimethyl 2-[1-[(phenylcarbonyl)amino]-2(1H)-quinolinyl]-2-butenedioate.     

Reaction of selenobenzophenones with olefins. Formation of 1H-2-benzoselenopyrans. Reaction of 1H-2-benzoselenopyrans with diazoalkanes

Selenobenzophenone reacts as a diene with dimethyl acetylenedicarboxylate (DMAD) to lead to dimethyl 1H-1-diphenylmethyl-1-phenyl-2-benzoselenopyran-3,4-dicarboxylate (5c) in moderate yield; the initial [4 + 2] cycloaddition is followed by the addition of another 1 mol equiv of selenobenzophenone. The reaction might proceed through carbene insertion of the primary cycloadduct. On the other hand, 4,4'-dimethoxyselenobenzophenone combines as a diene with DMAD furnishing dimethyl 1H-1-p-methoxyphenyl-6-methoxy-2-benzoselenopyran-3,4-dicarboxylate (4a). The reaction of benzoselenopyran derivative (4) with diaryldiazomethanes afforded another type of carbene insertion product.     

4,5-Dihydroxyimidazolidin-2-ones in an α-ureidoalkylation reaction of N-(carboxyalkyl)-, N-(hydroxyalkyl)-, and N-(aminoalkyl)ureas 3. α-Ureidoalkylation of N-[2-(dimethylamino)ethyl]urea

α-Ureidoalkylation of N-[2-(dimethylamino)ethyl]urea with 1,3-unsubstituted, 1,3-dialkyl-, and 1,3-dimethyl-4,5-diphenyl-4,5-dihydroxyimidazolidin-2-ones(thiones) was systematically studied. Hitherto unknown N-[2-(dimethylamino)ethyl]glycolurils and their hydrochlorides were synthesized. The yields of the target glycoluril hydrochlorides decreased on going from 1,3-H₂- to 1,3-dialkyl-4,5-dihydroxyimidazolidin-2-ones and increased with the introduction of phenyl groups at the positions 4 and 5 of the starting 4,5-dihydroxyimidazolidin-2-one. X-ray diffraction study showed that 2-[2-(dimethylamino)ethyl]glycoluril crystallizes in the form of a conglomerate.     

Efficient Synthesis of [1,3]Oxazino[3,2‐f]phenanthridine Derivatives by a Novel 1,4‐Dipolar Cycloaddition Involving a Phenanthridine–Dimethyl Acetylenedicarboxylate Zwitterion and Aromatic Aldehydes

An efficient synthesis of [1,3]oxazino[3,2‐f]phenanthridine derivatives via a three‐component reaction of phenanthridine, dimethyl acetylenedicarboxylate (DMAD), and aromatic aldehydes is described. This novel method is complementary to the classical Huisgen 1,4‐dipolar cycloaddition in that it is well‐suited to the preparation of [1,3]oxazino[3,2‐f]phenanthridines.     

Synthesis of Some 3-Substituted 1,2-Dihydroindoles

The reaction of 4-oxo-2-(2-oxo-1,2-dihydroindol-3-ylidene)hydrazone-1,3-thiazin-6-methyl carboxylate 2 with hydrazine hydrate in methanol gave 4-oxo-2-(2-oxo-1,2-dihydroindol-3-ylidene)hydrazone-1,3-thiazin-6-carbonylhydrazine 3. Furthermore, the reaction of 3 with carbon disulfide and then hydrazine hydrate afforded 3-[6-(4-amino-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-3-yl)-4-oxo-1,3-thiazin-2-yl] hydrazone-1,3-dihydroindol-2-one 5. the latest reacted with DMAD to give {6-hydroxy-3-[4-oxo-2-(2-oxo-1,2-dihydroindol-3-ylidene)hydrazone-1,3-thiazin-6yl]-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-ylidene}methoxycarbonylmethylene 6.     

Reaction between naphthols and dimethyl acetylenedicarboxylate in the presence of phosphites. Synthesis of stable oxa-2 lambda 5-phosphaphenanthrenes,and benzochromene derivatives

The reaction of dimethyl acetylenedicarboxylate (DMAD) with 2-naphthol in the presence of trimethyl or triphenyl phosphite leads to stable dimethyl oxa-2 lambda 5-phosphaphenanthrene derivatives in good yields. The reaction of DMAD and trimethyl phosphite in the presence of 1-naphthol or 8-hydroxyquinoline leads to dimethyl 2-(dimethoxyphosphoryl)-3-(1-hydroxy-2-naphthyl)succinate or dimethyl 2-(dimethoxyphosphoryl)-3-(8-hydroxyquinolin-7-yl)-succinate in excellent yields. Using triethyl phosphite and DMAD in the presence of 2-naphthol or 1-naphthol produces methyl 3-oxo-2,3-dihydro-1H-benzo[f]chromene-1-carboxylate or methyl 2-oxo-3,4-dihydro-2H-benzo[h]-chromene-4-carboxylate in excellent yields.     

One-Pot Synthesis of Novel Spiro Pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine Derivatives

In a one-pot synthesis, 1′-methyl-2,3″-dioxo-5″-aryl-1,2,5a″,7″,8″,9a″-hexahydro-5″H,6″H-dispiro[indole-3,2′-pyrrolidine-3′,2″-pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine]-4′-carboxylic acid methyl ester was prepared via the sequential reaction of 4-aryl-octahydro-pyrano[2,3-d]pyrimidine-2-thione, dimethyl acetylenedicarboxylate (DMAD), and a mixture of isatin and sarcosine. All the novel spiro compounds, in moderate yields, were characterized thoroughly by infrared, NMR, mass spectromentry, and elemental analysis together with x-ray crystallographic analysis.     

Synthesis and reaction of alpha-dithiolactone

Treatment of di-tert-butylthioketene S-oxide (5 a) with Lawesson reagent at room temperature resulted in the formation of 3,3-di-tert-butylthiirane-2-thione (4 a) in high yield. The oxidation of 4 a with mCPBA (mCPBA=m-chloroperbenzioc acid) gave 3,3-di-tert-butylthiirane-2-thione S-oxide (6) almost quantitatively. The reactions of 4 a with dimethyl acetylenedicarboxylate (DMAD) and benzyne afforded dimethyl 2-(2,2,4,4-tetramethylpentan-3-ylidene)-1,3-dithiole-4,5-dicarboxylate (13) and 2-(2,2,4,4-tetramethylpentan-3-ylidene)benzo[d][1,3]dithiole (15), respectively, in high yields, suggesting that 4 a is an excellent 1,3-dipole. The reaction of 4 a with ethylenebis(triphenylphosphine)platinum (16) gave dithiolato-platinum complex (22) in high yield. The structure of 22 was determined by X-ray crystallographic analysis.     

Interaction of Alkyl 5,6-Dialkyl-2-amino-3-cyano-4-pyridinecarboxylates with O-Nucleophiles. Synthesis of 6,7-Dialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones

The reaction of alkyl 5,6-dialkyl-2-amino-3-cyano-4-pyridinecarboxylates with certain O-nucleophiles was investigated, as a result of which 6,7-dialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones were synthesized.     

α-Thioureidoalkylation of functionally substituted ureas: I. Tandem cyclization and esterification in reactions of <Emphasis Type="Italic">N</Emphasis>-(carboxyalkyl)ureas with 1,3-dialkyl-4,5-dihydroxy-4,5-diphenylimidazolidine-2-thiones in alcohols

Acid-catalyzed reactions of N-(carboxyalkyl)ureas with 1,3-dialkyl-4,5-dihydroxy-4,5-diphenylimidazolidine-2-thiones in methanol or propan-2-ol led to the formation of previously unknown ω-(4,6-dialkyl-2-oxo-3a,6a-diphenyl-5-thioxooctahydroimidazo[4,5-d]imidazol-1-yl)alkanoic acids and their methyl and isopropyl esters. The structure of some esters was proved by X-ray analysis. Methyl (4,6-diethyl-2-oxo-3a,6adiphenyl-5-thioxooctahydroimidazo[4,5-d]imidazol-1-yl)acetate showed anxiolytic effect.     

Synthesis of 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids

Nitration of 2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-one gave its 5-nitro derivative which was subjected to alkylation with dimethyl sulfate, diethyl sulfate, and benzyl(dimethyl)phenylammonium chloride. The resulting 1,3-dimethyl-, 1,3-diethyl-, and 1,3-dibenzyl-5-nitro-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones were reduced to the corresponding 1,3-dialkyl-5-amino-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones, and the latter reacted with itaconic acid to produce 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids. 1-(2-Oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acid was obtained by analogous reaction with 5-amino-2,3-dihydro-1H-imidazo[4,5-b]-pyridin-2-one.     

Preparation of 3-(2H-pyran-2-on-6-yl)indolizines and the diels-alder reactions with some olefinic and acetylenic dienophiles

3-(2H-Pyran-2-on-6-yl)indolizines 6a-d were prepared by 1,3-dipolar cycloaddition reactions of N-(2H-pyran-2-on-6-yl)methylpyridinium bromides 5a,b with dimethyl acetylenedicarboxylate (DMAD). All of the cycloaddition reactions of 6b with N-phenylmaleimide, p-benzoquinone, and DMAD took place at the 2-pyrone ring to give 3-substituted indolizines.     

6-[(Dimethylamino)methylene]amino-1,3-dimethyluracil: A versatile aza-diene substrate for cycloaddition and michael-type reactions

6-[(Dimethylamino)methylene]amino-1,3-dimethyluracil 1 undergoes formal [4+2] cycloaddition reactions with electron deficient olefins to give pyrido[2,3-d]pyrimidines. With DMAD or azodicarboxylates Michael addition occurs leading to pyrrolo[3,4-c]pyridines (X-ray analysis) and theophylline derivatives.     

Two-step α-ureidoalkylation of ureas with 4,5-dihydroxyimidazolidin-2-ones

Two-step α-ureidoalkylation of ureas with various 4,5-dihydroxyimidazolidin-2-ones gave novel 1,3-dialkyl-4,5-bis(3-alkylureido)-, 1,3-dialkyl-4,5-bis[3-(2-pyrimidyl)ureido]-, or 1,3-dialkyl-4,5-bis(3,3-dialkylureido)imidazolidin-2-ones and ensembles of three imidazolidine rings. The structure of 4,5-bis(2-oxoimidazolidin-1-yl)imidazolidin-2-one was confirmed by X-ray diffraction data. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 140–145, January, 2007.