M. P. Egorov

σ-Anionic complexes of 1,3,5-trinitrobenzene with R3E groups (E = Si, Ge, Sn; R = Me, Et, Ph) and the routes of their transformations

Abstract Anionic σ-complexes, [TNB - ER 3 ] - M + , were obtained by the reaction of 1,3,5-trinitrobenzene (TNB) with R 3 EM (E = Si, Ge, Sn; R = Me, Et, Ph; M = Li, K). Their reactions with CH, NH and OH acids, CBr 4 and N -bromosuccinimide were studied. The mechanism of these transformations was proposed. It was found that in the reaction of Me 3 SnM with 2,4,6-trinitroanisole the latter acts as an alkylating agent, it also exhibits this property towards the other nucleophiles. σ-Complexes [TNB - ER 3 ] - M + , where M = K, Cs, in solution undergo irreversible rearrangement into the metal 3,5-dinitrophenolates. The mechanism for such processes and reactions of R 3 SnM with nitroaromatic compounds in general, are discussed.

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.

Formation of picrates in the reactions of picryl halides with the salts Me3SnM (M=Li, K, Cs), carbanions, and borates

The reactions of the picryl halides PicX (X = F, Cl) with the salts Me/sub 3/SnM (M = Li, K, Cs), 9-fluorenylpotassium, and borates of the type Me/sub 4/NBR/sub 4/ (R = Bu, CH/sub 2/SiMe/sub 3/, CH/sub 2/.GeMe/sub 3/) in THF at 0-5/sup 0/C in a vacuum were studied. In the reaction of PicF with Me/sub 4/NBBu/sub 4/ both in THF and in DMSO 1,3 sigma complex I is formed along with the picrate. Its structure was proved by the PMR and UV spectra, as well as by elemental analysis. The sigma complex (I) decomposes to PicONMe/sub 4/ with time.