K. S. Nosov

Cycloaddition of dialkylgermoles: synthesis and structures of 2,2,3,3-tetracyano-1,4,5,6-tetraphenyl-7-germanorborn-5-enes

Cycloaddition reactions of 1,1-dicyclopropyl-2,3,4,5-tetraphenyl-1-germacyclopentadiene (3) with dehydrobenzene, tetracyanoethylene, cyclooctyne, or dimethyl acetylenedicarboxylate as well as of 1,1-dimethy-2,3,4,5-tetraphenyl-1-germacyclopentadiene (4) and 2,3,4,5-tetraphenyl-1-germacyclopentadiene (5) with tetracyanoethylene or cyclooctyne were studied. Diels—Alder adducts of germoles3, 4, and5 with tetracyanoethylene were prepared. The structures of these adducts were established by X-ray diffraction analysis and their thermal and photochemical stabilities were examined.

Electron density distributions in substituted 2,3,4,5-tetraphenyl- 1-germacyclopenta-2,4-dienes studied by NMR spectroscopy

The signals in the13C NMR spectra of 2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-dienes (R1=R2=H, Me,cyclo-C3H5, SiMe3, SnMe3, R1=Me, R2=H, Cl) were completely assigned using 2D NMR spectroscopy. The pattern of the variation of the chemical shifts in the13C NMR spectra indicates that the effects of substituents R1 and R2 on the heterocycle and on the phenyl groups are of inductive rather than mesomeric origin and include the direct through-space polarization of bonds (field effect).

13C NMR study of 2,3,4,5-tetraphenylsilole dilithium salt

The complete assignment of the signals in the13C NMR spectra of 2,3,4,5-tetraphenyl-1-R1,R2-1-silacyclopenta-2,4-dienes (R1=R2=H, Me) and of the dianion of lithium salt [(PhC)4Si]2−·2Li+ was carried out by 2D NMR spectroscopy.

Correlation NMR spectroscopy of 1,1-dichloro-2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-diene

Assignment of all of the signals in the1H and13C NMR spectra of 1,1-dichloro-2,3,4,5-tetraphenyl-l-germacyclopenta-2,4-diene has been carried out using two-dimensional NMR spectroscopy.

The first example of metallation of an organogermanium hydride with an alkali metal under mild conditions: synthesis of 2,3,4,5-tetraphenyl-1,1-bis(trimethylsilyl)-1-germa-2,4-cyclopentadiene

ambient temperature for 1.5 h, and then it was extracted with ether. The ethereal extracts were washed with water and dried over Na2SO 4. After removal of the solvent and recrystallization from MeOH, m-nitrotolan (0.189 g, 85 %) was obtained.

Electrochemical study of redox properties of 2,3,4,5-tetraphenyl-1-heterocyclopenta-2,4-dienes Ph4C4ER1R2 (E = Si, Ge, Sn). A new method for generation of tetraphenylgermole dianion

The electrochemical behavior of the sila-, germa-, and stannacyclopentadienes (metalloles) was studied by cyclic voltammetry. The oxidation and reduction mechanisms of these heterocyclic compounds were investigated. A new method for generation of tetraphenylgermole dianion involving the electrochemical reduction of the corresponding dichlorogermole is proposed. Electrochemical oxidation of the metallole dianions was first studied taking tetraphenylgermole dianion as an example.

Synthesis and reactivity of germanium heterocycles containing germanium-tin bonds

Previously unknown stannyl-substituted germanium heterocycles, 1, 1 -bis(trimethylstannyl) 2,3,4,5-tetraphenyl-l-germacyclopenta-2,4-dienc and 1,1-bis(trimethylstannyl)-3,4-dimethyl-1-germacyclopent-3-ene were synthesized, and their photolysis and chemical transformations were Studied.