(Z,Z)-Muconaldehyde reacted with primary amines to give N-substituted-2(2'-oxoethyl)-pyrroles, which were reduced to N-substituted-2-(2'-hydroxyethyl)-pyrroles by sodium borohydride. The pyrrole-forming reaction is exhibited by valine and its methyl ester, and is being developed with terminal valine in hemoglobin as a means of dose monitoring (Z,Z)-muconaldehyde, a putative metabolite of benzen...

Calix[4]pyrroles having extended aromatic cavities have been functionalized with 4 ureas in the para position of their meso phenyl substituents. This elaboration of the upper rim was completed in 2 synthetic steps starting from the alpha,alpha,alpha,alpha-tetranitro isomer of the calix[4]pyrrole obtained in the acid catalyzed condensation of p-nitrophenyl methyl ketone and pyrrole. In dichlorom...

BACKGROUND The Birch reduction of electron rich pyrroles does not occur readily. However, dissolving metal reduction with zinc under acidic conditions gives 3-pyrrolines (2,5-dihydropyrroles) in reasonable yield. This dissolving metal reduction was first reported by Knorr and Rabe in 1901 but since then has only been reported for the reduction of electron rich pyrroles. RESULTS The partial re...

Calix[4]pyrroles such as meso-octamethylcalix[4]pyrrole 1 have been extensively studied as anion and ion-pair receptors over recent years. Subsequently ‘strapped’ calix[4]pyrroles, pioneered by Lee and Sessler, have been synthesised that contain a single linker between distal meso-positions. These compounds have increased 15 affinity for anions relative to the parent macrocycle. Recently there ...

The synthesis of N-arylated pyrroles and indoles is documented, as well as their functionalization by deprotonative metallation using the base in situ prepared from LiTMP and ZnCl2·TMEDA (1/3 equiv). With N-phenylpyrrole and -indole, the reactions were carried out in hexane containing TMEDA which regioselectively afforded the 2-iodo derivatives after subsequent iodolysis. With pyrroles and indo...

A sequential process strategy was introduced for the synthesis of 2,3,4,5-tetrasubstituted pyrroles by the formation of benzoin from the corresponding aromatic aldehyde and followed by condensation reaction with 1,3-dicarbonyl compounds and ammonium acetate in the presence of diethylene glycol-bis(3-methylimidazolium) dihydroxide as catalyst in refluxing ethanol. The recycled catalyst could be ...

The CuX (X = I, Br, Cl, CN)-mediated cyclization-halogenation and cyclization-cyanation reactions of beta-hydroxyalkynes and o-alkynylphenol and -aniline derivatives give rise to 3-halo- and 3-cyanofuro[3,2-b]pyrroles, 3-iodo-, 3-bromo-, and 3-cyanobenzofurans, and 3-cyanoindoles, respectively.

Pyrrole-aryl derivatives are important due to their unique biological activities in medicinal chemistry. We now report a new oxidative biaryl coupling for pyrroles and indoles toward various arenes using a hypervalent iodine reagent and an appropriate stabilizer for pyrrolyl iodonium intermediates. The reactions readily provide a variety of desired coupling products in good yields.

A base-catalyzed selective cycloisomerization of 3-aza-1,5-enynes is developed. This transformation provides a facile access to highly functionalized 2-azabicyclo[3.2.0]hept-2-enes and sulfonyl vinyl-substituted pyrroles. The chemoselectivity was controlled by the substituent pattern of the substrates.