Computational investigations of ligand-directed selectivities in Ullmann-type coupling reactions of methanol and methylamine with iodobenzene by β-diketone- and 1,10-phenanthroline-ligated CuI complexes are reported. Density functional theory calculations using several functionals were performed on both the nucleophile formation and aryl halide activation steps of these reactions. The origin of ligand-directed selectivities in N- versus O-arylation reactions as described in a previous publication (J. Am. Chem. Soc. 2007, 129, 3490−3491) were studied and explained. The selectivities observed experimentally are derived not from initial CuI(nucleophile) complex formation but from the subsequent steps involving aryl halide activation. The arylation may occur via single-electron transfer (SET) or iodine atom transfer (IAT), depending on the electron-donating abilities of the ligand and nucleophile. Mechanisms involving either oxidative addition/reductive elimination or σ-bond metathesis are disfavored. SET mec...

Computational Explorations of Mechanisms and Ligand-Directed Selectivities of Copper-Catalyzed Ullmann-Type Reactions

Peracids have gained interest in the water treatment over the last few decades. Peracetic acid (CH3CO3H) has already become an accepted alternative disinfectant in wastewater disinfection whereas p...

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Peracids in water treatment : a critical review

The first highly Z- and enantioselective class of ring-opening/cross-metathesis reactions is presented. Transformations are promoted in the presence of <2 mol % of chiral stereogenic-at-Mo monoaryloxide complexes bearing an adamantylimido ligand that are prepared and used in situ. Reactions involve meso oxabicyclic substrates and afford the desired pyrans in 50-85% yield and up to >98:<2 enantiomer ratio. Importantly, the desired chiral pyrans thus obtained bear a Z olefin either exclusively (>98:<2 Z/E) or predominantly (>or=87:13 Z/E).

Highly Z- and Enantioselective Ring-Opening/Cross-Metathesis Reactions Catalyzed by Stereogenic-at-Mo Adamantylimido Complexes

The Pd-catalyzed condensation of 2-bromostyrene and 2-chloroaniline derivatives yields stable diphenylamine intermediates, which are selectively converted to five-, six-, or seven-membered heteroaromatics (indoles, carbazoles, acridines, and dibenzazepines). The selectivity of these intramolecular transformations is uniquely ligand-controlled and offers efficient routes to four important classes of heterocycles from a common precursor.

Synthesis of Heterocycles via Pd-Ligand Controlled Cyclization of 2-Chloro-N-(2-vinyl)aniline: Preparation of Carbazoles, Indoles, Dibenzazepines and Acridines

Epoxy resin will continue to be in the forefront of many thermoset applications due to its versatile properties. However, with advancement in manufacturing, changing societal outlook for the chemic...

Multifunctionality in Epoxy Resins

In recent decades, a large number of reports related to the synthesis of N, O, and S containing heterocycles have appeared owing to a wide variety of their biological activity The metal catalyzed synthesis of heterocycles is becoming an important and highly rewarding protocol in organic synthesis Palladium-mediated cyclization reactions have been recognized as some of the simplest and useful tools for regio- as well as stereoselective syntheses of carbo- and heterocyclic compounds This review focuses on the use of palladium as a catalyst for the synthesis of nitrogen containing five-membered heterocylces fused with other heterocycles It describes the formation of different types of heterocyclic rings

Palladium Catalysts: Synthesis of Five-Membered N-Heterocycles Fused with Other Heterocycles

A review on high-throughput synthesis, deposition of thin films and properties of polyaniline

Microwave-Assisted Synthesis: Fused Five-Membered N-Heterocycles

Palladium-catalyzed approach to the synthesis of five-membered O-heterocycles

In recent decades, a large number of reports related to synthesis of N-, O- and S-containing heterocycles have appeared owing to a wide variety of their biological activity. The metal-catalyzed synthesis of heterocycles is becoming an important and highly rewarding protocol in organic synthesis. This review focuses on the use of metal as a catalyst for the synthesis of nitrogen-containing heterocycles. It describes the formation of higher-membered heterocyclic rings.

Navjeet Kaur

Papers

Palladium Catalysts: Synthesis of Five-Membered N-Heterocycles Fused with Other Heterocycles

A review on high-throughput synthesis, deposition of thin films and properties of polyaniline

Microwave-Assisted Synthesis: Fused Five-Membered N-Heterocycles

Palladium-catalyzed approach to the synthesis of five-membered O-heterocycles

Metal catalysts: applications in higher-membered N-heterocycles synthesis