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The synthesis of pyrrolidinoindolines is described. The scope of this method is explored and a model to rationalize the sense of stereoselection is advanced.

The synthesis of pyridinylpyrrole derivatives via the palladium-catalyzed reaction of acetylpyridines with methyleneaziridines is described. The presence of a ketone group in the pertinent position would make it possible to lead to the ring closing reaction.

The oxidative coupling of beta-carbonyl imines and allyltrimethylsilane with CTAN were examined in CH (sub 3) CN and CH (sub 2) Cl (sub 2). Combining allyltrimethylsilane with CTAN and a beta-carbonyl imine produces good yields of highly substituted silylated pyrroles.

The thermal isomerization studies with phosphorous-substituted aminoallenes are presented. The substituent effects on the rate and periselectivity of the thermal transformations are explored.

A metal-free, modular, and direct synthesis of 1,2,3,4-tetrasubstituted pyrroles from simple and commercially available components has been developed. The synthetic protocol embodies two coupled domino processes and is neatly accomplished in a one-pot manner according to the new chemical efficiency paradigm and this method can be applied in the fields of combinatorial chemistry, diversity-oriented synthesis and drug research.

Two different paladium (0)-catalyzed cyclizations leading to substituted pyrrolidines and 3-azabicyclo [3.1.0] hexanes allenes is studied. The allenenes are extremely useful substrates for palladium catalyzed cyclization to hetrocycles and furthermore the latter reaction of palladium-catalyzed cyclopropanation of allenes with double bond, which shows a novel reactivity of allenes.

A simplified and practical procedure for the electrophilic amination of heterocycles is discovered and developed using NH2Cl, a reagent that is easily prepared from inexpensive precursors. In this procedure pyrroles and indoles containing a variety of substitution is aminated on nitrogen.

An efficient approach to rigid tricyclic nitrogen heterocycles via sequential and tandem Ugi/intramolecular Diels-Alder (IMDA) cycloaddition of pyrrole is described. The one-pot Ugi four-component condensation (4CC) reaction is used as the key transformation to prepare trienes with a carboxamide substituent on the tether.

The use of tin complexation for the isolation and purification of 1,9-diacyldipyrromethanes is described. The selectivity of complexation of a variety of dipyrromethane species and the scope of complexation with a family of 1,9-diacyldipyrromethanes is characterized.

Three pulse infrared nonlinear studies of the N-H mode of pyrrole in carbon tetrachloride were carried out. Essential features of the N-H dynamics that include the population relaxation time, the orientational diffusion coefficients and the N-H vibrational frequency correlation function were obtained.

Methyl pyrrole-2-carboxylate (MPC), pyrrole-2-carbaldehyde (PC), methyl N-methylpyrrole-2-carboxylate (MPC-NMe), and N-methylpyrrole-2-carbaldehyde (PC-NMe) are investigated. The experimental and theoretical results show that for all the species investigated, the s-cis conformer is dominant in solution, and it is more stable than the s-trans conformer.

The photophysics and electrochemistry of an important class of laser dyes namely pyrromethene dyes (PM), is investigated. The dye radical cation, which displays a sharp absorption band at 410 nm, is found to be insensitive toward oxygen. Electron transfer involving the reduction of oxygen and producing superoxide radical anion is suggested.

Research has been conducted on substituted pyrroles. The authors describe regioselective synthesis of these compounds carried out via cycloisomerization of (Z)-(2-En-4-ynyl)amines.

Research has been conducted on ester-containing 5-carboxyl-5-methyl-1-pyrroline N-oxides. The estimated rate constants for these oxides at acidic and neutral pH for the reaction of ester-containing 5-carboxyl-5-methyl-1-pyrroline N-oxides with superoxide have been achieved via the use of ferricytochrome c.

The oxidation products in acetonitrile of hexapyrrolylbenzene (HPyB) and hexakis (3-octylpyrrolyl) benzene (HOPyB), two star-shaped compounds consisting of 6-fold N-pyrrolyl-substituted benzenes are characterized by MALDI-TOF. These products result from intramolecular coupling of pyrrolyl residues without dimer or polymer products.

The poly(vinylpyrrolidone) (PVP)-water solutions of 60-80 wt percent PVP apparently do not freeze when cooled far below the expected freezing point. The large amount of rapidly appearing and disappearing sharp peaks in the small-angle X-ray scattering (SAXS) region was observed confirming their origin.

An unnatural hydrophobic base, pyrole-2-carbaldehyde (Pa), is developed as a specific pairing partner of 9-mehylimidazo[(4,5)-b]pyridine (Q). The concept of a hydrophobic base pair is applied to the creation of unnatural base pairs for the expansion of the genetic alphabet.

The barrier to the internal rotation around the C-N bond in N-trifluoroacetylpyrrolidine (TFAPYR) was characterised using dynamic NMR spectroscopy. The pyrrolidine ring substituent in TFAPYR reduces the bulkiness around the C-N amide bond, stabilizing the ground state and increasing the value of the internal rotation barrier, deltaG(super ++)(sub 298), compared to N,N-dimethyl- and N,N-diethyltrifluoroacetamide.

The mechanism of the action of interstrand cross-linking agents and the design of new types of cross-linking agents is investigated. A novel type of DNA interstrand cross-linking agent by synthesizing dimes of a pyrrole (Py)/Imidazole (Im)-diamide-CPI conjugate, ImPyLDu86, connected using seven different linkers is developed.

Three types of processes are examined, namely, monomer loading, polymerization and removal of unreacted monomers. It is observed that these processes are affected by the presence of oxygen and are photosensitive. A variety of oxidizing agents are used to effect polymerization including Fe(super 3+), H2O2, ammonium persulfate, and UV irradiation.

A new and potentially more generalizable strategy that is based on metal coordination is reported. The synthesis and fluoride anion recognition properties of the fused dipyrrolylquinoxaline phenanthroline derivative and its ruthenium(II) and cobalt (III) complexes are presented.

Theoretical research on the spectroscopy and protonation energies of ionic species related to the neutral pyrrola-aza-aromatic bases is carried out, using Density Functional Theory (DFT) and its time dependent form (TDDFT). In the ionic species the skeleton localized (+) and (-) charge in the protonated and deprotonated species is shown to have a strong perturbation of the Pi-electronic states.

The ESR broadening that is observed in polypyrrole (Ppy), which is caused due to the presence of molecular oxygen is examined. It could be concluded that the physically adsorbed oxygen within the polypyrrole film may be responsible for line width variation.

Pyrrolizidine alkaloids are nitrogen-fused bicyclo[3.3.0] octanes and have long attracted synthetic interest due to their relatively simple structural features and wide range of pharmacologic activity. Many synthetic methods for these alkaloids rely on an efficient approach to functionalized 2-pyrrolidinones.

Dienes 23 and 54, prepared from epoxy alcohol 9 via oxazolidinones 15 and 51, underwent ring-closing metathesis with Grubbs's catalyst to give azacyclooctene 26 and 55. Attempts to effect ring-closing metathesis of dienes 37,38, and 46 were unsuccesful, suggesting that, while one allylic oxygen substituent can be tolerated by Grubbs's catalyst, two cannot.

On starting from N-allyl substituted 2-indolecarbaldehydes and exploiting the intramolecular nitrone cycloaddition methodology, a number of the title fused-ring indole derivatives in racemic as well as enantiopure form were synthesized. The results show some degree of variability, particularly as the final hydrogenation step is concerned, there is no doubt that they are satisfactory in view of the planned target.

Studies done on quino-and isoquinoporphyrins, which are obtained, from commercially available 6-nitroquinoline and 5-nitroisoquinoline by using the Barton-Zard pyrrole synthesis and the MacDonald '3+1' methodology are presented. A zinc chelate of the isoquinoporphyrin system demonstrates a high degree of regioselective intermolecular interaction that may be of value in the development of molecular recognition studies.

Preparation of 1,2-diary(heteroaryl)pyrroles and -3-methylpyrroles in a two-step procedure from N-allylbenzotriazoles via intramolecular oxidative cyclization in the presence of Pd(II) catalyst is reported. Results reveal that no cyclization occurs when Pd(II) catalyst is used alone.

The amount of helicity is studied to find its dependency on the length and more specifically the conformational preferences of the alkyl spacer unit. The studies indicate the importance of conformational preferences of the beta-beta alkyl spacer group plays in the coordination algorithm of self-assembly to form dipyrromethene based complexes.

Efficient routes to 10-azatriquinacene and 10-azatriquinadiene respectively eight and seven steps from pyrrole are described. Azatriquinacene 2 is analyzed as its trifluoroacetate salt but could be converted to the free base by addition of aqueous hydroxide and extraction into dichloromethane.

Dinuclear zinc bis-ProPhenol complex is used as an efficient catalyst to conduct asymmetric Friedel-Crafts alkylations of unprotected pyrroles with nitroalkenes in order to prepare 2-substituted and 2,5-disubstituted pyrroles with an asymmetric carbon atom in the [alpha]-position. The avoidance of using N-protecting groups in pyrrole alkylations has increased the efficiency by which substituted pyrroles are synthesized.

A new cryptand-like porphyrinoid assembled with three dipyrrylpyridine chains is described in order to show how positive cooperativity is realized in binding monofunctional ligands. The dual binding mode of this receptor has responded to structurally different ligands.

The experimental evaluation of the anion-[pi] interaction using, as a model system, calyx[4]pyrroles in solution is explored. The solid packing of the [alpha], [alpha], [alpha], [alpha] isomer of calyx[4]pyrrole-resorcine hybrid 1 and tetra-methylamonium chloride [Cl.sup.-] x 2a is controlled by their relative stoichiometry in solution.

A mild tandem aza-Payne/hydroamination reaction of aziridinols mediated by dimethylsulfoxonium methylide is reported which yields highly functionalized pyrrolidine ring systems in one pot at room temperature. The resulting strained enamide products are potentially useful synthons for the rapid construction of densely substituted pyrrolidines and pyrrolidinones for use in natural product synthesis.

The description of a new photochemically mediated intramolecular metathesis sequence of pyrroles is presented. The reaction has revealed to proceed through two sequential wavelength-dependent reactions involving [2+2] cycloaddition at 220-280 nm followed by a retro-[2+2] of the resulting cyclobutane at wavelengths longer than this.

A new Au-catalyzed cascade cycloisomerization of propargylic derivatives of N-containing heterocycles into fused pyrrole-containing heterocycles is reported. The reaction has proceeded through alkyne-vinylidene isomerization with concomitant 1,2-migration of H, silyl-, and stannyl groups, as well as previously unknown 1,2-migration of a germyl group, thereby giving easy access to a variety of C-2 functionalized heterocycles.

A unique process is presented in which two different [sp.sup.3] C-H bonds are selectively activated under the same conditions to construct polysubstituted pyrroles from commercially available phenethylamines. During the transformation, twelve protons and two nitrogen atoms are removed, at least twelve bonds are cleaved and five new bonds are constructed in one pot.

A new organocatalyzed enantioselective tandem Michael-aldol reaction is disclosed by furnishing synthetically useful thiochromenes in high yields (72-97%) and good to high enantionselectivities (85-95% ee). A broad range of alpha,beta-unsaturated aldehydes and 2-mecraptobenzaldehydes could be tolerated in the process.

The enantioselective total synthesis of (-)-rhazinilam is reported which demonstrates the success of this reaction design using Au(I)-catalyzed pyrrole-allene additions. Asymmetric Au(I)-catalyzed pyrrole additions to enantioenriched allenes afford a unique entry to optical active heterocycles.

The use of pyrroles as nucleophiles in the Pd asymmetric allylic alkylation (AAA) and the use of such a process for asymmetric synthesis of agelastatin A are described. By varying the functional groups at the 2-position of pyrroles, either regioisomer of the piperazinones can be accessed efficiently and enantioselectively and the total synthesis of agelastatin A was completed in a short and concise way.

The synthesis and characterization of binuclear silver(I) complex of macrocyle that is formed as a result of a homotropic cooperative ion pair insertion wherein the receptors binds two metal cations and anions are reported. The spectrum of a mixture of 1 and ~1.3 equiv of Ag(O(sub 2)CCH(sub 3)) in THF-d(sub 8) revealed the presence of two species and under conditions of intermediate binding site saturation, the coordination of first Ag(I) cation appears to activate the system towards further coordination.

An efficient aerobic palladium (II) oxidation system for C-H bond functionalization of sensitive molecules under ambient conditions is reported. The catalyst system enables a direct regioselective pyrrole C-H bond alkenylation and annulation process where reaction at either the C2 or C3 position can be effected.

The bulk synthesis of microns long electrically conducting polypyrrole nanotubes having 6 nm average pore diameter by chemical oxidative polymerization of pyrrole is described. These nanotubes undergo a spontaneous redox reaction with noble metal ions under mild aqueous conditions, resulting in deposition of 3-8 nm size particles of Ag, Au, Pd and more on the tube surface.

A diastereoselective and efficient synthesis of highly substituted delta1-pyrroline-5-carboxylic acid scaffolds through a silver(I)-catalyzed [3 + 2] cycloaddition reaction is developed. The exo selectivity complements the endo-selective cycloaddition of related acyclic azomethine ylides very well.

A rapid and convenient seeding method to chemically synthesize bulk quantities of microns-long, 60-90 nm thick nanofibers of polypyrrole is described. The findings have a potential to be leveraged beyond conducting polymers to embrace the broad class of precipitation polymerization reactions.

A study is conducted to show that pyrroles can be considered as the product of three basic building blocks coupled via palladium catalysis providing a modular method to construct these heterocycles with facile diversity and high atom economy. Experiments directed towards understanding of the role of P(o-tolyl)(Sub 3) in this catalysis, as well as the application of this approach to other heterocyclic targets are progressing.

The stereosyntheses of dihydropyrrolidines and dihydroazepines are demonstrated in Rh2(OAc)(sub 4)-catalyzed reactions. Broad selections of catalysts that are suitable for ylide generation are surveyed, in the course of investigating catalytic ylide-derived reactions of vinyldiazo compounds with imines.

A study is conducted on the doubly N-confused hexaphyrin structures that are quite distinct, wherein the two adjoining metals are situated in a wide conjugated alpha-electron pool. Finally for bis-metal in the closely related surface, a different set of porphyrinoids comprise of more than four pyrrolic elements in the middle are contemplated.