Center for Magnetic Resonance

S. Lednev, A. Sirick, E. Pliss, A. Rusakov, N. Shvyrkova, A. Ivanov.

“Influence of solvation on the kinetics of methyl methacrylate oxidation inhibited by aromatic amines”

Reac. Kinet. Mech. Cat., 2015, 116,43-50

DOI:10.1007/s11144-015-0881-9

The kinetics of methyl methacrylate oxidation inhibited by aromatic amines in media of different polarities was studied. The complexing parameters in systems “oxidation substrate—aromatic amine—solvent” using IR and NMR spectroscopy were found. The correlations between inhibited oxidation rate constant and the polarity of the medium were obtained using Kirkwood–Onsager equation.

A.S. Pankova, A.Yu. Stukalov, M.A. Kuznetsov

“Synthesis of 2‑(Hetero)aryl-5-(trimethylsilylethynyl)oxazoles from 2 (Hetero)arylacrylic Acids”

Org. Lett., 2015, accepted

DOI:10.1021/acs.orglett.5b00009

A three-step method for the synthesis of 2-(hetero)-aryl-5-(trimethylsilylethynyl)oxazoles is described. Easily accessible bis(trimethylsilyl)acetylene and acrylic acid derivatives are used as starting materials for the preparation of mono- and disubstituted 5-(trimethylsilyl)pent-1-en-4-yn-3-ones. Oxidative phthalimido-aziridination of these enynones provides the key 2-acyl-1-phthalimido-aziridines that are further utilized in the thermal expansion of the three-membered ring to furnish the target functionalizable oxazoles.

P.R. Golubev, A.S. Pankova, M.A. Kuznetsov

“Regioselective Transition-Metal-Free Synthesis of 2‑(Trimethylsilylmethylene)pyrrol-3-ones by Thermal Cyclization of Acetylenic Enamines”

J. Org. Chem., 2015, accepted

DOI:10.1021/acs.joc.5b00398

Acetylenic enamines generated in situ from readily available enynones and primary amines undergo thermal cyclization in diphenyl ether providing easy access to 4-aryl-2-(trimethylsilylmethylene)-1,2-dihydro-3H-pyrrol-3-ones. This reaction is inherently versatile, allowing for variations of substituents in both enynone and amine. Full regioselectivity along with short reaction time (1−2 h) and simple workup afford single products in good to excellent isolated yields. Fluorescent properties of the obtained compounds were studied.>

S.N. Britvin, A. Lotnyk

“Water-Soluble Phosphine Capable of Dissolving Elemental Gold: The Missing Link between 1,3,5-Triaza-7-phosphaadamantane (PTA) and Verkade’s Ephemeral Ligand”

J. Am. Chem. Soc., 2015, accepted

DOI:10.1021/jacs.5b01851

We herein describe a tricyclic phosphine with previously unreported tris(homoadamantane) cage architecture. That water-soluble, air- and thermally stable ligand, 1,4,7-triaza-9-phosphatricyclo[5.3.2.14,9]tridecane (hereinafter referred to as CAP) exhibits unusual chemical behavior toward gold and gold compounds: it readily reduces Au(III) to Au(0), promotes oxidative dissolution of nanocrystalline gold(0) with the formation of water-soluble trigonal CAP−Au(I) complexes, and displaces cyanide from [Au(CN)2]− affording triangular [Au(CAP)3]+ cation. From the stereochemical point of view, CAP can be regarded as an intermediate between 1,3,5-triaza-7-phosphaadamantane (PTA) and very unstable aminophosphine synthesized by Verkade’s group: exahydro-2a,4a,6a-triaza-6bphosphacyclopenta[cd]pentalene. The chemical properties of CAP are likely related to its anomalous stereoelectronic profile: combination of strong electron-donating power (Tolman’s electronic parameter 2056.8 cm−1) with the low steric demand (coneangle of 109°). CAP can be considered as macrocyclic counterpart of PTA with the electron-donating power approaching that of strongest known phosphine electron donors such as P(t-Bu)3 and PCy3. Therefore, CAP as sterically undemanding and electronrich ligand populates the empty field on the stereoelectronic map of phosphine ligands: the niche between the classic tertiary phosphines and the sterically undemanding aminophosphines.

A.P. Molchanov, Yu.V. Malinina, R.R. Kostikov, A.V. Stepakov

“Regioselective Cycloaddition of C,N-Diarylnitrones to Arylallenes and of N-Aryl-C-carbamoylnitrones to Methyl Buta-2,3-dienoate”

Russ. J. Org. Chem, 2015, 51, 368-372

DOI:10.1134/S1070428015030136

Cycloadditions of C,N-diarylnitrones to non-activated arylallenes and of N-aryl-C-carbamoylnitrones to methyl buta-2,3-dienoate regioselectively afforded mixtures of diastereoisomeric substituted 4-methylideneisoxazolidines.

A.V. Stepakov, A.G. Larina, A.P. Molchanov

“Isomerization of Dimethylenecyclopropanes in Benzofulvenes in the Presence of Lewis Acids”

Russ. J. Org. Chem, 2015, 51, 210-213

DOI:10.1134/S1070428015020128

1,1-Diaryl-2-(1-methylethylidene)-3-methylenecyclopropanes in the presence of Lewis acid isomerize in benzofulvene derivatives.