scholarly journals Lead tetraacetate oxidation of the Diels-Alder adduct of 7-dehydrocholestryl acetate with maleic anhydride

2000 ◽  
Vol 65 (3) ◽  
pp. 147-156 ◽  
Author(s):  
Lidija Bondarenko-Gheorghiu ◽  
Ljubinka Lorenc ◽  
Mihailo Mihailovi]
Keyword(s):  
Double Bond ◽  
Maleic Anhydride ◽  
Total Yield ◽  
Diels Alder ◽  
Lead Tetraacetate ◽  
Starting Material ◽  
Large Excess ◽  
Pyridine Solution ◽  
Alder Adduct

The Diels-Alder adduct (3), obtained by cycloaddition of 7-dehydrocholesteryl acetate (1) and maleic anhydride (2), was heated at ca. 90?C with a large excess of lead tetraacetate in pyridine solution for 5h. Under these conditions, compound 3 underwent lactonization with the participation of the olefinic ?6-double bond to give two isomeric monolactone derivatives, 9 and 10 (in a total yield of ca. 6%), and the bislactone product 11 (in 11.5% yield). The starting material was recovered in 36% yield.

Reactions of N-3′-furylbenzamide with some dienophiles

1979 ◽  
Vol 57 (3) ◽  
pp. 314-317 ◽  
Author(s):  
John N. Bridson
Keyword(s):  
Double Bond ◽  
Maleic Anhydride ◽  
Methyl Acrylate ◽  
Diels Alder ◽  
First Case ◽  
Dimethyl Maleate ◽  
Related Compounds ◽  
Alder Adduct

N-3′-Furylbenzamide gives a conventional Diels–Alder adduct with maleic anhydride but with dimethyl maleate and methyl acrylate further reactions take place at the enamide grouping of the initially formed adducts. Compounds have been isolated in which molecules of an alcohol, used as solvent, or the starting furan have added to the double bond of the 1:1 adducts. In the first case unstable alkoxyamides are formed; in the second stable 2:1 adducts result from a novel uncatalysed addition to the double bond of the enamide. The stereochemistry of these and related compounds is discussed.

Model Compounds Related to Saquayamycin. Attempts to Oxygenate the A/B Ring Junction

2002 ◽  
Vol 55 (5) ◽  
pp. 343 ◽  
Author(s):  
M. A. Apponyi ◽  
J. H. Bowie ◽  
B. W. Skelton ◽  
A. H. White
Keyword(s):  
Double Bond ◽  
Maleic Anhydride ◽  
Good Yield ◽  
Ring Opening ◽  
Diels Alder ◽  
Aromatic System ◽  
Model Compounds ◽  
Similar Treatment ◽  
Ring Junction

The aim of this project was to attempt to find a method for introducing the cis-dihydroxyl substitution at the A/B-ring junction of model compounds related to the saquayamycins. The Diels-Alder reactions of maleic anhydride and bromomaleic anhydride with 5,5-dimethyl-3-vinylcyclohexa-1,2-dienyl acetate gave the two required endo-adducts in good yield, namely (octahydrobenzo[e]isobenzofuran-9-yl acetate (6) and (octahydrobenzo[e]isobenzofuran-9-yl acetate (9). Each of these was converted into the B-ring mono-epoxide, namely (H-benzo[e]oxireno-2,3-furan-1-yl acetate (7) and a mixture of two racemic diastereoisomers of 9a-bromo-3,3-dimethyl-7,9-dioxoperhydrobenzo[e]oxi- reno[2,3-f]isobenzofuran-1-yl acetate (12), respectively. It was then hoped to deprotonate both (7) and (12) at the 9a position in order to effect migration of the 8,9 double bond to the 9,9a position. Reaction of (7) with a mild base (pyridine) did not effect any reaction. Similar treatment of (12) did remove the 9a proton, but it also effected ring opening of the epoxide, followed by dehydration and dehydrobromination to give an excellent (but unwanted) yield of the aromatized system (±)-7,7-dimethyl-1,3-dioxo-1,3,5,7-tetrahydrobenzo (e]isobenzofuran-9-yl acetate. Dehydrobromination of (9), and deprotonation of the 9a position, similarly formed the aromatic system (e]isobenzofuran-9-yl acetate (11) in good yield.

scholarly journals Radical Polymerization of Furan with Maleic Anhydride through the Diels—Alder Adduct

1974 ◽  
Vol 6 (2) ◽  
pp. 121-131 ◽  
Author(s):  
Bunzo Kamo ◽  
Isamu Morita ◽  
Satoshi Horie ◽  
Shijo Furusawa
Keyword(s):  
Maleic Anhydride ◽  
Radical Polymerization ◽  
Diels Alder ◽  
Alder Adduct

ChemInform Abstract: Synthesis of Chiral Polyfunctionalized Cyclopentanes from the Diels-Alder Adduct of Furan and Maleic Anhydride.

ChemInform ◽  
2000 ◽  
Vol 31 (38) ◽  
pp. no-no
Author(s):  
Richard T. Brown ◽  
Simon B. Jameson ◽  
Dehimi Ouali ◽  
Peter I. Tattersall
Keyword(s):  
Maleic Anhydride ◽  
Diels Alder ◽  
Alder Adduct

Synthetic Studies on Viridin Skeleton through Regio- and Stereoselective Functionalization of the AE-Ring Moiety

Synlett ◽  
2021 ◽  
Author(s):  
Shuhei Hori ◽  
Sho Ishida ◽  
Go Ito ◽  
Koji Sugiyama ◽  
Chiharu Yuki ◽  
...  
Keyword(s):  
Maleic Anhydride ◽  
Ring Structure ◽  
Diels Alder ◽  
Furan Derivative ◽  
Epoxide Opening ◽  
Synthetic Studies ◽  
Stereoselective Epoxidation ◽  
Key Steps ◽  
Alder Adduct

4,5,6,7-Tetrahydroisobenzofurans, corresponding to the AC(D)E ring structure of viridin and equipped with required substituents on the A-ring, were synthesized via the Diels-Alder adduct of a furan derivative and maleic anhydride with high regio- and stereoselectivities. The key steps of this work include the regioselective opening of the tetrahydrofuran, stereoselective epoxidation, and AlMe3-mediated regioselective epoxide opening followed by stereoselective C-methylation.

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