Introduction In 1950, the chemists Otto Paul Hermann Diels, from Germany, and Kurt Alder, originally born in Prussia and then moved to Germany after World War I, received the Nobel Prize in chemistry for the discovery of a new way to synthesize cyclic molecules. Aptly titled the Diels-Alder Cycloaddition Reaction, this new mechanism allowed conjugated dienes to undergo addition reactions with a...

A kinetic study of DNA-based catalytic enantioselective Friedel-Crafts alkylation and Michael addition reactions showed that DNA affects the rate of these reactions significantly. Whereas in the presence of DNA, a large acceleration was found for the Friedel-Crafts alkylation and a modest acceleration in the Michael addition of dimethyl malonate, a deceleration was observed when using nitrometh...

In the present work, the regioselectivity for a series of Diels–Alder reactions (4 reactions) has beenstudied using hardness, electrophilicity and polarizability of products.Furthermore,thermodynamicand kinetic calculations have been done. In all results predicted pararegioisomer is more favorableregioisomerinthese investigated reactions.All calculations have been done at the DFT-B3LYP/6-31G(d)...

New reactions and reagents that allow for multiple bond-forming events per synthetic operation are required to achieve structural complexity and thus value with step-, time-, cost-, and waste-economy. Here we report a new class of reagents that function like tetramethyleneethane (TME), allowing for back-to-back [4 + 2] cycloadditions, thereby amplifying the complexity-increasing benefits of Die...

A family of furoquinolines were efficiently obtained through a tandem acetalization/cycloisomerization process catalyzed by (5 mol%) silver imidazolate polymer and triphenylphosphine, and diversity was brought by the use of 7 different alcohol groups. From these furoquinolines, 3 examples of reduced derivatives could be obtained (d.r. up to 94 : 6), 10 different spiroketal derivatives by hetero...

A systematic study of the Diels–Alder reaction α-nitrocinnamate was performed. The p-substituted with 2,3-dimethyl-1,3-butadienes smoothly proceeded regardless p-substituent, which either an electron-donating or -withdrawing group. control revealed that isomerized during reaction. Danishefsly’s diene (1-methoxy-3-trimethylsiloxy-1,3-butadiene) facilitated cycloaddition under mild conditions to ...

3,3'-Dicarboxy-4,4'-diaminobiphenyl was synthesized from Onitrobenzoic acid following standard procedures. Diazotization of this compound with isoamylnitrite, under approtic condition gave diphenyl-4,4'-bis-diazonium-3,3'-dicarboxylate and subsequent thermal decomposition of this diazonium compound produced 3,4,3',4'-tetradehydrobiphenyl (bisbenzyne) as a reactive intermediate. Bisbenzyne w...

A practical, enantioselective synthetic route to a key precursor to the tetracycline antibiotics is reported. The route proceeds in nine steps (21% yield) from the commercial substance methyl 3-hydroxy-5-isoxazolecarboxylate. Key steps in the route involve enantioselective addition of divinylzinc to 3-benzyloxy-5-isoxazolecarboxaldehyde and an endo-selective intramolecular furan Diels-Alder cyc...

Supercritical CO 2 blown foams of poly(ε-caprolactone) (PCL) covalent networks are developed through a two-step strategy by taking advantage the thermo-reversible Diels–Alder cycloaddition between furan and maleimide.

A variety of organocatalysts were screened for the catalysis of the naphthoquinone monoketal Diels-Alder reaction. In this study we found that Schreiner's thiourea catalyst 10 and Jacobson's thiourea catalyst 12 facilitate the cycloaddition of the sterically hindered naphthoquinone monoketal dienophile 3 with diene 4. The use of thiourea catalysis allowed for the first time the highly selective...