The reaction of steroid 2,4-dienes with acetylenes

Peter Yates; Françoise M. Walliser

doi:10.1139/v76-504

The reaction of steroid 2,4-dienes with acetylenes

Canadian Journal of Chemistry ◽

10.1139/v76-504 ◽

1976 ◽

Vol 54 (22) ◽

pp. 3508-3516 ◽

Cited By ~ 7

Author(s):

Peter Yates ◽

Françoise M. Walliser

Keyword(s):

Diels Alder ◽

The Other ◽

Dimethyl Acetylenedicarboxylate ◽

Methyl Propiolate ◽

Lower Temperature

Reaction of 2,4-cholestadiene, 2,4-androstadien-17-one, or 3-trimethylsiloxy-2,4-cholestadiene with dimethyl acetylenedicarboxylate or methyl propiolate in boiling xylene results in the cleavage of rings A and B and the formation of 4-(2-arylethyl)-5-isopropenyl-7a-methyltetrahydroindane derivatives. They are considered to be formed via Diels–Alder addition of the acetylene to the steroid diene followed by a retro-Diels–Alder cleavage of the resulting bicyclo[2.2.2]octadiene system. Attempts to isolate the Diels–Alder adducts by carrying out the additions at lower temperature were unsuccessful, since no reaction occurred. However, when 2,4-androstadien-17-one was treated with dicyanoacetylene in boiling benzene, it was possible to isolate a mixture of two stereoisomeric Diels–Alder adducts containing the bicyclo[2.2.2]octadiene system in ring A; this was converted in boiling xylene to a retro-Diels–Alder product analogous to the products obtained with the other acetylenic dienophiles.

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Annelated furans. XI. The reactions of 2-vinylfurans with acetylenic esters

Australian Journal of Chemistry ◽

10.1071/ch9731059 ◽

1973 ◽

Vol 26 (5) ◽

pp. 1059 ◽

Cited By ~ 16

Author(s):

WJ Davidson ◽

JA Elix

Keyword(s):

Diels Alder ◽

Dimethyl Acetylenedicarboxylate ◽

Acetylenic Ester ◽

Acetylenic Esters ◽

Methyl Propiolate ◽

Diene System ◽

Alder Adduct ◽

Ene Addition

In general dimethyl acetylenedicarboxylate and methyl propiolate have been found to react with 2-vinylfurans to give the corresponding dimethyl benzofuran-4,5-di-carboxylates and methyl benzofuran-4- carboxylates respectively. In several instances dimethyl acetylenedicarboxylate did not react exclusively with the exocyclic diene system of the 2-vinylfuran and here the corresponding dimethyl 3,6-epoxy-3-vinyl-3,6-dihydrophthalates were obtained by Diels-Alder addition to the furanoid diene system. At 80� 2-vinylfuran and dimethyl acetylenedicarboxylate formed the 1 : 2 adduct (11), the formation of which can be interpreted as involving an ene addition of a second mole of the acetylenic ester to the initially formed Diels-Alder adduct.

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Some 6,6-disubstituted 2,4-cyclohexadien-1-ones and the facial selectivity in their Diels–Alder reactions with dimethyl acetylenedicarboxylate

Canadian Journal of Chemistry ◽

10.1139/v89-007 ◽

1989 ◽

Vol 67 (1) ◽

pp. 37-47 ◽

Cited By ~ 4

Author(s):

Peter Yates ◽

Anabela Gomes ◽

D. Jean Burnell ◽

Dong Dao Cong ◽

Jeffery F. Sawyer

Keyword(s):

Spectroscopic Method ◽

Diels Alder ◽

The Other ◽

Dimethyl Acetylenedicarboxylate ◽

X Ray ◽

Product Ratio ◽

X Ray Crystallography ◽

Facial Selectivity ◽

Chemical Correlation ◽

The Individual

6,6-Disubstituted 2,4-cyclohexadien-1-ones can be prepared by dibromination–bisdehydrobromination of the corresponding 6,6-disubstituted 2,2-dibromocyclohexanones. Such dienes undergo Diels–Alder reactions with dimethyl acetylenedicarboxylate to give 3,3-disubstituted 5,6-di(methoxycarbonyl)bicyclo[2.2.2]octa-5,7-dien-2-ones; when the substituents at C-6 in the dienones are different, two diastereomers of the adducts are formed in a ratio dependent on the "facial selectivity" in the Diels–Alder reactions. For the cases where one of the 6-substituents is methyl and the other is methoxycarbonyl, acetoxymethyl, dibromomethyl, or dichloromethyl it has been established via X-ray crystallography and chemical correlation that the endo-3-methyl/exo-3-methyl product ratio is 3.0, 0.9, 8, and 6, respectively. The origin of these differences is discussed briefly and a spectroscopic method for the assignment of structures to the individual diastereomers is proposed. Keywords: Diels–Alderreactions, substituted 2,4-cyclohexadien-1-ones, facial selectivity, dimethyl acetylenedicarboxylate.

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Reaction of 2-[(E)-styryl]Quinazolin-4(3H)-one with Acetylenic Esters: Formation of Unexpected N-3 Alkenylation Products

Journal of Chemical Research ◽

10.3184/030823405774309212 ◽

2005 ◽

Vol 2005 (7) ◽

pp. 429-431 ◽

Cited By ~ 2

Author(s):

Tapasi Chatterjee ◽

Subhagata Chattopadhyay ◽

Ranjan Mukhopadhyay ◽

Basudeb Achari ◽

Santu Chakraborty ◽

...

Keyword(s):

Hydrogen Bonds ◽

Alder Reaction ◽

Diels Alder ◽

Dimethyl Acetylenedicarboxylate ◽

Acetylenic Esters ◽

X Ray ◽

Methyl Propiolate ◽

Diels Alder Reaction ◽

Centrosymmetric Dimers

Attempted hetero Diels–Alder reaction with 2-[(E)-styryl]quinazolin-4(3H)-one (1) and dimethyl acetylenedicarboxylate (2) resulted in unexpected N-3 alkenylation products, 2-[(E)-styryl]-3-[(Z)-1,2-bis(methoxycarbonyl)vinyl]quinazolin-4(3H)-one (4a) and 3-[(E)-1,2-bis(methoxycarbonyl) vinyl] 2-[(E)-styryl]-quinazolin-4(3H)-one (4b) in low yield. Treating 1 and 2-methylquinazolin-4(3H)-one (9) with methyl propiolate (7) also furnished N-3 alkenylation products in low yield. The structure of 4b has been established by X-ray analysis. The molecules of 4b are linked by intermolecular C-H. … N hydrogen bonds into centrosymmetric dimers forming R22 (12) rings.

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Diels-Alder Reactions of Vinyl Derivatives of [1]Benzothieno[3,2-b]furan

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990389 ◽

1999 ◽

Vol 64 (2) ◽

pp. 389-407 ◽

Cited By ~ 12

Author(s):

Pavel Pihera ◽

Hana Dvořáková ◽

Jiří Svoboda

Keyword(s):

Double Bond ◽

Carboxylic Acid ◽

Dicarboxylic Acid ◽

Diels Alder ◽

Dimethyl Acetylenedicarboxylate ◽

Carboxylic Group ◽

Methyl Propiolate ◽

Vinyl Derivatives ◽

Hydrolysis Of ◽

Derivatives Of

2-Vinyl- (2) and 3-vinyl[1]benzothieno[3,2-b]furan (3) react with dimethyl acetylenedicarboxylate, methyl propiolate, maleic anhydride, or acrylonitrile endo-selectively as dienes to afford new [1]benzothieno[3,2-b][1]benzofuran derivatives 7-20. cis-Anhydrides 13 and 18 were transformed into dimethyl esters 21 and 22, respectively. It was shown that the base-catalyzed hydrolysis of 13 and 18 is accompanied by rearrangement of double bond in 13 and cis/trans isomerization of carboxylic group. Diesters 21 and 22, and nitriles 20 and 24 were aromatized by treatment with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Selective monodecarboxylation of [1]benzothieno[3,2-b][1]benzofuran-8,9-dicarboxylic acid (26) and [1]benzothieno[3,2-b][1]benzofuran-6,7-dicarboxylic acid (27) afforded [1]benzothieno[3,2-b][1]benzofuran-8-carboxylic acid (28) and [1]benzothieno[3,2-b][1]benzofuran-7-carboxylic acid (29), respectively.

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The Diels-Alder reaction of some styrenes and 2,2-dimethylchromenes with acetylenic esters

Australian Journal of Chemistry ◽

10.1071/ch9691721 ◽

1969 ◽

Vol 22 (8) ◽

pp. 1721 ◽

Cited By ~ 5

Author(s):

JA Diment ◽

E Ritchie ◽

WC Taylor

Keyword(s):

Linear Structure ◽

Alder Reaction ◽

Diels Alder ◽

Dimethyl Acetylenedicarboxylate ◽

Acetylenic Esters ◽

Methyl Propiolate ◽

Diels Alder Reaction ◽

Derivatives Of

Examples of the Diels-Alder reaction between some derivatives of styrene and of 2,2-dimethylchromene and dimethyl acetylenedicarboxylate and methyl propiolate, leading ultimately to fully aromatic derivatives, are described. Yields are generally low and the synthesis has limited utility. However, the n.m.r, spectrum of the product from acronycine dimethyl acetylenedicarboxylate is such as to establish the angular rather than the linear structure for acronycine.

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Polar Diels-Alder Reactions Under Microwave Irradiation Employing Different Heterocyclic Compounds as Electrophiles

Mini-Reviews in Organic Chemistry ◽

10.2174/1570193x15666180608083925 ◽

2019 ◽

Vol 16 (6) ◽

pp. 527-543 ◽

Cited By ~ 1

Author(s):

Pedro M.E. Mancini ◽

Carla M. Ormachea ◽

María N. Kneeteman

Keyword(s):

Organic Synthesis ◽

Heterocyclic Compounds ◽

Ionic Conduction ◽

Theoretical Calculations ◽

Cycloaddition Reaction ◽

Diels Alder ◽

The Other ◽

Conventional Heating ◽

Protic Ionic Liquids ◽

Solvent Free Conditions

During the last twenty years, our research group has been working with aromatic nitrosubstituted compounds acting as electrophiles in Polar Diels-Alder (P-DA) reactions with different dienes of diverse nucleophilicity. In this type of reaction, after the cycloaddition reaction, the nitrated compounds obtained as the [4+2] cycloadducts suffer cis-extrusion with the loss of nitrous acid and a subsequent aromatization. In this form, the reaction results are irreversible. On the other hand, the microwave-assisted controlled heating become a powerful tool in organic synthesis as it makes the reaction mixture undergo heating by a combination of thermal effects, dipolar polarization and ionic conduction. As the Diels-Alder (D-A) reaction is one of the most important process in organic synthesis, the microwave (MW) irradiation was applied instead of conventional heating, and this resulted in better yields and shorter reaction times. Several substituted heterocyclic compounds were used as electrophiles and different dienes as nucleophiles. Two experimental situations are involved: one in the presence of Protic Ionic Liquids (PILs) as solvent and the other under solvent-free conditions. The analysis is based on experimental data and theoretical calculations.

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