Synthesis of Functionalized 2,3-Dihydropyrroles Promoted by Samarium Diiodide

Abstract

The intermolecular reductive coupling of 1,1-diaryl-2,2-dicyanoethylenes or 1,1-diaryl-2-cyano-2-ethoxycarbonylethylenes with substituted benzalazines induced by samarium diiodide was studied. Functionalized 2,3-dihydropyrroles were prepared in good yields under neutral and mild conditions.     

Reductive Amination of the Lysine N ε-Amino Group Leads to a Bivalent Glyco-Amino Acid Building Block Suited for SPPS

Aiming at the synthesis of structurally altered glycopeptides to probe multivalency effects in carbohydrate recognition, a glyco-amino acid building block was prepared, carrying a bivalent carbohydrate branching unit. This new mannosylated lysine derivative was shown to be fully suitable for solid-phase peptide synthesis.     

Square integrability of representations on p-adic symmetric spaces

A symmetric space analogue of Casselman's criterion for square integrability of representations of a p-adic group is established. It is described in terms of exponents of Jacquet modules along parabolic subgroups associated to the symmetric space.     

Palladium-catalyzed benzoin-mediated redox process leading to biaryls from aryl halides

An expedient synthetic procedure of biaryl derivatives was developed using a palladium-catalyzed, benzoin-mediated redox process from aryl halides. Various biaryls were synthesized in good yields in short time.     

Titanium (IV) as an essential promoter in the asymmetric addition of diethylzinc to aldehydes catalyzed by aminonaphthol and imine ligands based on 3-substituted binaphthol

By using indirect reductive amination and condensation, two types of aminonaphthol and imine ligands based on 3-substituted binaphthol have been synthesized, respectively. When their catalytic effectiveness was tested by the ethylation of aldehydes with diethylzinc, titanium tetraisopropoxide was found essential to get good results with ee up to 90%.     

Reductive immobilization and long-term remobilization of radioactive pertechnetate using bio-macromolecules stabilized zero valent iron nanoparticles

Carboxymethyl cellulose-and starch-stabilized nZVI nanoparticles were prepared and showed high efficiency for reductive immobilization of ⁹⁹TcO₄^- in simulated groundwater.     

Principe de densité pour les groupes rèuctifs

The main goal of this Letter is to give a new proof of a result conjectured by D. De George and N. Wallach and proved by P. Deborne and to extend it to the S-arithmetic setting. The proof is based on a density principle.     

Quantum integrable models of interacting bosons and classical r-matrices with spectral parameters

Using the technique of classical $r$-matrices with spectral parameters we construct a general form of quantum Lax operators of interacting boson systems corresponding to an arbitrary simple (or reductive) Lie algebra. We prove quantum integrability of these models in the physically important case of $\mathfrak{g}=gl\left(n\right)$ and “diagonal” in the root basis classical $r$-matrices. We consider in detail two classes of non-skew-symmetric classical $r$-matrices with spectral parameters and obtain the corresponding quantum Lax operators and quantum integrable many-boson hamiltonians that generalize Bose–Hubbard dimer hamiltonians.     

An efficient synthesis of highly functionalized chiral lactams

A new method was developed to synthesize highly functionalized lactams via a one pot reductive amination/lactam formation reaction. This methodology is amenable for parallel synthesis and was used to prepare a large number of lactam analogs in a library format with good ee (de) retention.     

One-pot synthesis of chiral azetidines from chloroaldehyde and chiral amines

A variety of chiral azetidinepiperidines have been synthesized utilizing an expedient one-pot union of piperidine chloroaldehyde with chiral amines. This two step one-pot procedure provides access to an interesting set of compounds that retain the chiral purity of the starting chiral amine.