ChemInform Abstract: Moisture-Stable Dialkylimidazolium Salts as Heterogeneous and Homogeneous Lewis Acids in the Diels-Alder Reaction.

ChemInform ◽  
2010 ◽  
Vol 28 (33) ◽  
pp. no-no
Author(s):  
J. HOWARTH ◽  
K. HANLON ◽  
D. FAYNE ◽  
P. MCCORMAC
Keyword(s):  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction

Influence of Lewis Acids on the Diels–Alder Reaction. IV. Reaction of 2-Methyl- and 2-Phenylfuran with Ethyl Propiolate

1971 ◽  
Vol 49 (19) ◽  
pp. 3152-3157 ◽  
Author(s):  
A. W. Mcculloch ◽  
A. G. McInnes
Keyword(s):  
Methyl Acrylate ◽  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Methyl Propionate ◽  
Diels Alder Reaction ◽  
By Products

The AlCl3-promoted reactions of 2-methyl- and of 2-phenylfuran with ethyl propiolate afford as major products ethyl 5-hydroxy-2-methyl- and 2-phenylbenzoates (6a, 6b). Also isolated as minor by-products of these reactions are ethyl 3-(2-furyl-5-methyl)acrylate (5a), ethyl 3-(2-furyl-5-phenyl)acrylate (5b), ethyl 3,3-di(2-furyl-5-methyl)propionate (10a), ethyl 3,3-di(2-furyl-5-phenyl)propionate (10b), and ethyl 2-hydroxy-5-methylbenzoate (8a).

An examination of VANOL, VAPOL, and VAPOL derivatives as ligands for asymmetric catalytic Diels–Alder reactions

2006 ◽  
Vol 84 (10) ◽  
pp. 1487-1503 ◽  
Author(s):  
Douglas P Heller ◽  
Daniel R Goldberg ◽  
Hongqiao Wu ◽  
William D Wulff
Keyword(s):  
Asymmetric Catalysis ◽  
Methyl Acrylate ◽  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Asymmetric Catalytic ◽  
Diels Alder Reaction ◽  
Positive Cooperativity ◽  
Derivatives Of ◽  
Methyl Phenyl

Several derivatives of the vaulted biaryl ligand VAPOL were prepared and evaluated as chiral ligands for aluminum Lewis acids in the catalytic asymmetric Diels–Alder reactions of methyl acrylate and methacrolein with cyclopentadiene. The substituents on VAPOL were introduced into the 6- and 6′-positions in an effort to further extend the chiral pocket of the major groove, which contains the phenol functions at the 4- and 4′-positions. The set of four new ligands that have been prepared have the following groups introduced into the 6- and 6′-positions of VAPOL: bromide, methyl, phenyl and 3,5-di-t-butylphenyl. All of these ligands give lower asymmetric inductions than the unsubstituted VAPOL for the Diels–Alder reactions of both methyl acrylate and methacrolein. The positive cooperativity of added carbonyl compounds on the autoinduction in the Diels–Alder reaction of methyl acrylate and cyclopentadiene were also investigated with the VANOL and VAPOL ligands as well as the 6,6′-dibromo and 6,6′-diphenyl derivatives of VAPOL. Only the reaction with VAPOL showed any significant positive cooperativity. The reaction with VANOL was sluggish at –78 °C, but at higher temperatures, the reaction did exhibit positive cooperativity that was similar to that of VAPOL. Finally, no positive cooperativity was observed with the VAPOL ligand for the reaction of methacrolein and cyclopentadiene.Key words: Diels–Alder, asymmetric catalysis, vaulted biaryl ligands, VANOL, VAPOL.

Influence of Lewis acids on the Diels–Alder reaction. III. Rearrangement of dimethyl N-carbomethoxy-7-azabicyclo[2.2.1]2,5-heptadiene-2,3-dicarboxylate adducts to dimethyl N-carbomethoxy-3-aminophthalates

1970 ◽  
Vol 48 (9) ◽  
pp. 1472-1474 ◽  
Author(s):  
R. C. Bansal ◽  
A. W. McCulloch ◽  
A. G. McInnes
Keyword(s):  
Aluminum Chloride ◽  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Prolonged Treatment ◽  
Dimethyl Acetylenedicarboxylate ◽  
Diels Alder Reaction ◽  
Convenient Route

Aluminum chloride accelerates the Diels–Alder reactions of 2- or 2,5-substituted N-carbomethoxypyrroles with dimethyl acetylenedicarboxylate, and also catalyzes rearrangement of the N-carbomethoxy-7-azanorbornadiene adducts to 6- and 4,6-substituted dimethyl N-carbomethoxy-3-aminophthalates. Aromatization of the corresponding adduct of N-carbomethoxypyrrole only occurs on prolonged treatment with BF3. The procedure promises to be a convenient route for the synthesis of polysubstituted anilines.

scholarly journals New L-Serine Derivative Ligands as Cocatalysts for Diels-Alder Reaction

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Carlos A. D. Sousa ◽  
José E. Rodríguez-Borges ◽  
Cristina Freire
Keyword(s):  
Catalytic Activity ◽  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Reaction Yield ◽  
Catalytic Potential ◽  
Diels Alder Reaction ◽  
Good Ability ◽  
Medium Strength

New L-serine derivative ligands were prepared and tested as cocatalyst in the Diels-Alder reactions between cyclopentadiene (CPD) and methyl acrylate, in the presence of several Lewis acids. The catalytic potential of the in situ formed complexes was evaluated based on the reaction yield. Bidentate serine ligands showed good ability to coordinate medium strength Lewis acids, thus boosting their catalytic activity. The synthesis of the L-serine ligands proved to be highly efficient and straightforward.

ChemInform Abstract: [(PPh3)Ag(CB11H6Y6)] (Y: H, Br): Highly Active, Selective and Recyclable Lewis Acids for a Hetero-Diels-Alder Reaction.

ChemInform ◽  
2010 ◽  
Vol 33 (9) ◽  
pp. no-no
Author(s):  
Catherine Hague ◽  
Nathan J. Patmore ◽  
Christopher G. Frost ◽  
Mary F. Mahon ◽  
Andrew S. Weller
Keyword(s):  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Highly Active ◽  
Diels Alder Reaction

Influence of Lewis Acids on the Diels–Alder Reaction. VII. The Reaction of Furan with Ethyl Propiolate

1974 ◽  
Vol 52 (6) ◽  
pp. 1013-1018 ◽  
Author(s):  
A. W. McCulloch ◽  
D. G. Smith ◽  
A. G. McInnes
Keyword(s):  
Lewis Acids ◽  
Alder Reaction ◽  
Diels Alder ◽  
Product Ratio ◽  
Diels Alder Reaction

Reaction of furan and ethyl propiolate at 130° affords a low yield of 2,6-dicarbethoxy-9-oxatetracyclo[3.2.1.1.3,802,4]non-6-ene (4). This structure was confirmed by 1H and 13C n.m.r. spectroscopy. In the presence of AlCl3 the same addends give only a mixture of the Diels–Alder endo–endo10 and endo–exo11 diadducts. Isomer 11 is decomposed by AlCl3, the rate of decomposition, and therefore the product ratio 10:11, being as expected dependent on time, temperature, and reactant concentrations.

Influence of Lewis acids on the Diels–Alder reaction. II. Rearrangement of 1- and 1,4-substituted diethyl 7-oxabicyclo[2•2•1]2,5-heptadiene-2,3-dicarboxylate adducts to 4- and 4,6-substituted diethyl 3-hydroxyphthalates

1969 ◽  
Vol 47 (23) ◽  
pp. 4319-4326 ◽  
Author(s):  
A. W. McCulloch ◽  
B. Stanovnik ◽  
D. G. Smith ◽  
A. G. McInnes
Keyword(s):  
Lewis Acids ◽  
Room Temperature ◽  
Alder Reaction ◽  
Diels Alder ◽  
Substituted Phenols ◽  
Aryl Substituent ◽  
Diels Alder Reaction ◽  
Step Procedure ◽  
Direct Formation ◽  
Substituted Furans

Direct formation of 4- or 4,6-alkyl and aryl substituted diethyl 3-hydroxyphthalates from the correspondingly substituted Diels–Alder adducts of 2- or 2,5-substituted furans and diethyl acetylenedicarboxylate is promoted by AlCl3 in CH2Cl2 at room temperature. The first adduct of 2,5-diphenylfuran to be isolated has been obtained from the same reaction at −20°. The aromatic compounds can be obtained alternatively by treating the adducts with BF3 or H2SO4: where the adducts can be prepared by conventional means this two-step procedure has resulted in greatly improved yields. Adducts of furan and furfuryl alcohol are similarly converted to substituted phenols. HCl effected conversion only in the case of adducts carrying a bridgehead aryl substituent; in all other cases HCl added to the substituted double bond. The mechanism of the adduct rearrangement is discussed.

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