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Microwave-assisted Piloty-Robinson synthesis of 3,4-disubstituted pyrroles.

ABSTRACT: The synthesis of N-acyl 3,4-disubstituted pyrroles can be accomplished directly from hydrazine and an aldehyde via a Piloty-Robinson pyrrole synthesis. The use of microwave radiation for the cyclization and pyrrole formation greatly reduces the time necessary for this process and facilitates moderate to good yields from hydrazine for the corresponding 3,4-disubstituted products (5-12). By simple hydrolysis, the free N-H pyrroles can be accessed after the Piloty-Robinson reaction and then used directly in the synthesis of octaethylporphyrin (H2OEP, 14) and octaethyltetraphenylporphyrin (H2OETPP, 15).

SUBMITTER: Milgram BC

PROVIDER: S-EPMC1939979 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature

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Microwave-assisted Piloty-Robinson synthesis of 3,4-disubstituted pyrroles.

Milgram Benjamin C BC Eskildsen Katrine K Richter Steven M SM Scheidt W Robert WR Scheidt Karl A KA

The Journal of organic chemistry 20070414 10

The synthesis of N-acyl 3,4-disubstituted pyrroles can be accomplished directly from hydrazine and an aldehyde via a Piloty-Robinson pyrrole synthesis. The use of microwave radiation for the cyclization and pyrrole formation greatly reduces the time necessary for this process and facilitates moderate to good yields from hydrazine for the corresponding 3,4-disubstituted products (5-12). By simple hydrolysis, the free N-H pyrroles can be accessed after the Piloty-Robinson reaction and then used di ...[more]

PMID: 17432915

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