Calix pyrrole 3-substituted

Other calix[4]pyrroles for anion sensing include the mono-tetrathiafulvalene 168 <2003AGE187> and the meso-substituted 3,4,5-tribromopyrrole derivative 169 <2003CC1810>... 

Recent literature in the chemistry of calixpyrroles comprises the syntheses, characterization and complexation reactions of a series of binucleating Schiff-base calixpyrrole macrocycles <2007CEJ(A)3707> a study of the dynamics of calix[4]pyrrole and octafluorocalix[4]pyrrole as a function of the solvent and fluorine substitution <2007CEJ(A)1108> and oxygen reduction at dicobalt complexes of a Schiff base calixpyrrole ligand <2007AGE584>. 

Gale, P.A. Hursthouse. M.B. Light, M.E. Sessler, J.L. Warriner. C.N. Zimmerman. R.S. Ferrocene-substituted calix[4]pyrrole A new electrochemical sensor for anions involving CH anion hydrogen bonds. Tetrahedron. Lett. 2001, 442. 6759. 

Gale, P.A. Bleasdale. E.R. Chen, G.Z. Synthesis and electrochemical polymerisation of calix[4]pyrroles con- 30. taining TV-substituted pyiTole moieties. Supramol. Chem. 

B. Anion-Binding Properties of /9-Substituted Calix[4]pyrroles.267... 

B. ANION-BINDING PROPERTIES OF -SUBSTITUTED CALIX[4]PYRROLES... 

Concerning the functionalization of PPy by calixarene, the first attempts to electrochemically homopolymerize a calix[4]arene modified at its lower rim by a N-substituted pyrrole moiety... 

Many of the p-substituted calix[4]pyrroles known in the literature were likewise synthesized via a condensation strategy. Typically, a functionalized pyrrole bearing substituents on one or both of the p-pyrrolic positions is condensed with a ketone under acid catalyzed conditions. However, a number of mono-substituted calix[4] pyrroles have been prepared by a post-synthetic strategy. Here, a functional group, such as an ester, formyl, or iodine substituent, is introduced onto one of the P-pyrrolic positions within OMCP. In many cases, this is done by subjecting the calix[4]pyrrole to deprotonation with a strong base (e.g., n-butyl lithium), followed by the addition of the appropriate electrophile [9,10]. On the other hand, iodination has typically been achieved by reacting calix[4]pyrrole with iodine-[bis(trifluor-oacetoxy)iodo]benzene [11]. These functionalized systems have been elaborated further to create, inter alia, anion sensors or materials that may be attached to solid or polymeric supports. 

In 2002 Sessler et al. designed two cytosine-substituted calix[4]pyrrole conjugates with a cytosine moiety attached either at a p- or meso-pyrrolic position (43 and 44, Fig. 24.18). These hetero-calix[4]arene nucleobase conjugates were tested as nucleotide-selective carriers and as active components of nucleotide-sensing ion-selective electrodes [52]. 

The chiral tetraurea calix[4]pyrrole 28 was obtained by substituting one of the hydrogen atoms at the four benzylic methylenes of 23 by a methyl group (Fig. 32.12). 

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