A two-step protocol for the synthesis of highly substituted pyrroles in aqueous media and without catalyst is described. The first step is the dimerization of a 1,3-dicarbonyl compound by ceric ammonium nitrate/ultrasound to produce a tetracarbonyl derivative. This derivative is then combined with an amine in the absence of any catalysts to obtain the pyrrole via a PaalÁKnorr reaction. This route is an improvement when compared with classical methodologies toward Green Chemistry objectives.

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Terpenes U 0200Chemoselective Formation of 8,9-Epoxy-limonene. -A simple and efficient three step synthetic route for the preparation of 8,9-epoxylimonene in good yields and in > 99% purity without any trace of 1,2-epoxide-limonenes is described. -(ALMEIDA, Q. A. R.; JONES*, J. J.; Synth. Commun. 35 (2005) 10, 1285-1290; Inst. Quim., Univ. Fed. Rio de Janeiro,