mardi 13 février 2007

SYNTHESIS OF 3,4-disubstitutedpyrrole-2,5-dicarboxylate

The post of today is an elegant synthesis of tetrasubstituted pyrrole from a pyridazine ring, this synthesis has been described by Dale Boger et al. and require only zinc metal (9-20 equiv. and previously activated(1)) and acetic acid (0.09M), this transformation is performed in about 24h at room temperature with moderate to good yields (42-70%).


(1) Fieser, L. F.; Fieser, M. "Reagents for Organic Synthesis"; Wiley: New York, 1967; Vol. 1, p.
1276.

For more information about the procedure and the synthesis of pyridazine see:
Organic Syntheses, Coll. Vol. 9, p.335 (1998); Vol. 70, p.79 (1992).

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