T. V. Strelkova

β-Diphenylphosphorylated alkanones and related compounds: synthesis and structure

The reactions of diphenyl(diisopropyl)chlorophosphine with arylidene(heteroarylidene)-acetones and 3-benzylidenepentane-2,4-dione in the presence of acetic acid proceed at a high rate at room temperature to afford the corresponding β-diorganylphosphorylated alkanones and alkanediones in high yields. The reaction of diphenylchlorophosphine with 4-methoxybut-3-en-2-one and dibenzylideneacetone carried out under similar conditions at the equimolar reagent ratio can serve as a convenient method for the synthesis of unique β-diphenylphosphorylalkenones. The structures of compounds obtained were established by IR, Raman, and NMR spectroscopy and X-ray diffraction.

Synthesis and study of the structure of cage-like metallosiloxanes with pair combinations of 3d transition and alkaline earth metals

The selective replacement of Na ions in cage-like (Cu,Na) organosiloxanes in reactions with divalent metal halides was studied. The sandwich-like isomer [PhSiO2]6Cu4Na4[PhSiO2]6 forms the corresponding bimetallic complexes [PhSiO2]6Cu4M2[PhSiO2]6 (M = Cu, Zn, Mg, Sr, Ba) retaining a sandwich-like structure (in 60–90% yields) regardless of the metal ion size in MCl2. Under similar conditions, the reactions of the globular isomers [RSiO2]12Cu4Na4 (R = Ph, Me, Vin) with CuX2 (X = Cl or Br) afforded insoluble polymer products. The reaction in dioxane or THF in the presence of DMSO gave the crystalline globular-type metal complexes [RSiO2]12Cu4[CuX]4, in which Na ions are replaced by CuX groups. The compositions and structures of the synthesized metal complexes were studied by X-ray diffraction, elemental analysis, and destructive silylation combined with gel permeation chromatography and 1H NMR spectroscopy.

Dicarbonyl chelates from 1-cymantrenylalkylamides: formation, properties, and kinetics of the dark reaction with carbon monoxide

Photolysis of carboxamides with aminomethyl-, 1-aminoethyl-, and aminobenzylcymantrenes led to six-membered dicarbonyl chelates with the Mn—O bond, which are stable in solutions. In the presence of carbon monoxide, the chelates undergo a dark reverse reaction with the formation of the starting tricarbonyl complexes. It was found that the rate determining step of the thermal reaction of the chelates with CO was the chelate ring opening according to the SN1 mechanism of ligand substitution.

Orientation in the metalation of amide, carbamate, ureido, and allylic derivatives of cymantrene

The orientation in the metalation of monosubstituted carbamate-, amide-, ureido-, and allyl-containing derivatives of cymantrene was determined for the first time. The data obtained open up a synthetic route to polyfunctional 1,2- and 1,3-disubstituted cymantrenes. They can serve as the starting materials for the preparation of chelate complexes of (dicarbonyl)-(cyclopentadienyl)manganese, which hold promise as novel organometallic photochromes. A method for the synthesis of earlier unknown chiral derivatives of cymantrene with a quaternary carbon atom in position 1 of the side chain was proposed.

Bis(pentafluorophenyl)phosphinous acid in the synthesis of P,P-bis(pentafluorophenyl)phosphorylalkanones and -alkanediones

Addition of bis(pentafluorophenyl)phosphinous acid to α,β-alkenones and α,β,β’-alkene-diones in anhydrous Et2O (the solvent, in which the P-OH tautomeric form predominates) proceeds rapidly and regiospecifically at the C=C bond of the substrate at room temperature in the absence of catalysts. The reaction leads to bis(pentafluorophenyl)phosphorylated alkanones and alkanediones, as a rule, in the yields close to quantitative and can be considered as a highly efficient method for the synthesis of the corresponding functionalized phosphine oxides. The structures of obtained compounds were established by IR and NMR spectroscopy and X-ray diffraction analysis.

Synthesis and thermal properties of polydimethylsiloxanes modified by decyl and methylundecylenate substituents

A series of polydimethylsiloxanes modified by long-chain hydrocarbon substituents, including those containing terminal ester groups, was synthesized. The structures of the copolymers were confirmed by the data of 1H and 29Si NMR spectroscopy. The thermal properties of the copolymers were studied by differential scanning calorimetry. The change in the behavior of the copolymers is observed at the content of modifying units is >5 mol.% and the fluidity of the polymers is retained at the content of these units <15 mol.%.

Synthesis of polyfunctionalized methylphosphine oxides

N,N-Dialkylamino(diphenylphosphoryl)chloromethanes, a new type of organophosphorus compounds, were synthesized. On dissolving in polar and low polar solvents, N,N-dialkylamino(diphenylphosphoryl)chloromethanes dissociate spontaneously with the P—C bond cleavage to form the diphenylphosphinite anion Ph2PO−. This was confirmed by the reaction of N,N-dimethylamino(diphenylphosphoryl)chloromethane with electrophilic substrates to form the corresponding addition or substitution products of Ph2PO−. The capability of spontaneous generating the diphenylphosphinite anion considers accessible N,N-dimethylamino(diphenylphosphoryl)chloromethane as a synthetic equivalent of the diphenylphosphinite anion.

Synthesis and properties of quinazoline derivatives containing cymantrenyl group

The synthesis of new quinazoline derivatives with 2,3- and 4-positioned cymantrenyl fragment is described. Alkylation of 2-substituted quinazolin-4-ones with cymantrenylalkyl bromides on using K2CO3, potassium tert-butoxide, and sodium hydride as bases has been studied. It is established for the first time that condensation of 2-methylquinazolin-4-ones with aldehydes can cause elimination of the substituent at the nitrogen atom in position 3. The new cymantrene derivatives possess fluorescence properties.

Synthesis of 11-methyl-13-azabicyclo[7.3.1]trideca-3,10-diene, a macrobicycle with the 9b-azaphenalene carbon framework, based on the combination of allylboration and intramolecular metathesis

A four-step synthesis of 11-methyl-13-azabicyclo[7.3.1]trideca-3,10-diene, a potential precursor of the ladybugs´ defensive alkaloids precoccinelline and mirrhine, has been accom-plished. Treatment of 4-picoline with 5-hexenyl-1-lithium, triallylborane, and methanol led to the synthesis of trans-6-allyl-2-(hex-5-enyl)-4-methyl-1,2,3,6-tetrahydropyridine, which reacted with triallylborane upon heating to be converted to the cis-isomer. A subsequent cyclization of the cis-isomer of N-Boc derivative via the intramolecular metathesis using Grubbs II and Hoveyda—Grubbs II ruthenium catalysts furnished the target bridged macrobicycle. The structure of its hydrochloride was confirmed by single crystal X-ray diffraction studies. The optimal conditions for the metathesis reaction and the isolation of the macrobicyclic product were selected.

Photochromic transformations of cymantrenyl amides

Photochemical properties of N-acyl-substituted aminomethyl- and 1-aminoethylcymantrenes were studied for the first time. These compounds form photochromic systems in solutions due to the intermolecular exchange of ligands at the manganese atom.