Palladium(II)-Catalyzed Aerobic 1,2-Diacetoxylation of Conjugated Dienes

Fast and mild palladium(II)-catalyzed 1,4-oxidation of 1,3-dienes via activation of molecular oxygen with a designed cobalt(II) porphyrin.

The use of a Co(porphyrin)-amide ligand, , in the palladium(II)-catalyzed 1,4-diacetoxylation of conjugated dienes under O2 results in aerobic oxidation. The catalyst was highly active under O2, and the 1,4-diacetoxylation reaction could also be performed under air.

Cyclopolymerization of Conjugated Dienes

The formation of essentially saturated polymers containing fused cyclohexane rings is a characteristic of the polymerization of conjugated dienes under the influence of all cationic or Lewis acid catalysts. The amount of cyclic structures and non-terminal linear unsaturation is dependent upon the electron accepting ability of the catalyst, which may be greatly influenced by the nature of the so...

Synthesis of conjugated dienes via a biomimetic aerobic oxidative coupling of two C(vinyl)-H bonds.

Facile synthesis of dibranched conjugated dienes via palladium-catalyzed oxidative coupling of N-tosylhydrazones.

A facile and highly regioselective Pd-catalyzed oxidative coupling of N-tosylhydrazones providing efficient access to 2,3-disubstituted-1,3-butadienes has been developed. This process features readily available starting materials and mild reaction conditions. Further transformations of the obtained dibranched 1,3-dienes, through Diels-Alder reactions and indene synthesis, are also demonstrated,...

Catalyst-controlled regioselectivity in the synthesis of branched conjugated dienes via aerobic oxidative Heck reactions.

Pd-catalyzed aerobic oxidative coupling of vinylboronic acids and electronically unbiased alkyl olefins provides regioselective access to 1,3-disubstituted conjugated dienes. Catalyst-controlled regioselectivity is achieved by using 2,9-dimethylphenanthroline as a ligand. The observed regioselectivity is opposite to that observed from a traditional (nonoxidative) Heck reaction between a vinyl b...