- The first synthesis of organic diselenolates: Application to the synthesis of diorganyl diselenides
-
The addition of elemental selenium to organolithium compounds 1 or organic selenates 2 gives organic diselenolates 3. The reactions proceed by the insertion of two selenium atoms into the carbon-metal bonds or of one selenium atom into a selenolate. Evidence for the existence of n- butyldisilenol has also been obtained.
- Krief, Alain,Van Wemmel, Thierry,Redon, Martine,Dumont, Willy,Delmotte, Cathy
-
p. 2245 - 2247
(2007/10/03)
-
- Photoinduced Electron Transfer Initiated Activation of Organoselenium Substrates as Carbocation Equivalents: Sequential One-Pot Selenylation and Deselenylation Reaction
-
The investigation presented in this paper explores the mechanistic aspects and synthetic potentials of PET activation of organoselenium substrates.Fluorescence quenching of 1DCN* by a number of organoselenium compounds (RCH2SeR', 1-4), correlation of the fluorescence quenching rate constants with the oxidation potentials of 1-4, and the dependence of photodissociation quantum yields of 1-4 on their concentration suggests the occurence of electron transfer processes between 1DCN* and 1-4.Steady-state photolysis of 1-4 in the presence of 1DCN* leads to the efficient one-electron oxidative heterolytic dissociation of the carbon-selenium bond to produce the carbocation (RCH2(1+) or equivalent) and radical-centered selenium species (R'Se(.)) via the intermediacy of cation-radical .Nucleophilic assistance in the fragmentation of (RCH2SeR')(1+.) by methanol has been suggested on the basis of products obtained from the control PET reaction of neopentyl phenyl selenide (8).The synthetic utility of these findings has been demonstrated for the deselenylation (Table 4) as well as one-spot sequential selenylation-deselenylation (Table 5) reactions.
- Pandey, Ganesh,Soma Sekhar, B. B. V.
-
p. 7367 - 7372
(2007/10/02)
-
- Reactions of 2,4,6-Tri-t-butylphenyllithium with O-Alkyl Selenoformates: Intermediate Formation of 2,4,6-Tri-t-butylselenobenzaldehyde
-
2,4,6-Tri-t-butylphenyllithium reacts with O-alkyl selenoformates (1) at three different sites (i.e., the selenoformyl carbon, the selenoformyl hydrogen, and the selenium) to give 1,3,5-tri-t-butylbenzene, 2,4,6-tri-t-butylbenzaldehyde, 6,8-di-t-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzoselenin (11), bis(2,4,6-tri-t-butylphenylmethyl) di(and tri) selenides, bis(2,4,6-tri-t-butylphenyl) diselenide, and dibutyl diselenide depending on the reaction conditions and the alkyl group in 1.The formation of 11 is explained in terms of the intermediacy of 2,4,6-tri-t-butylselenobenzaldehyde, which is trapped by condensation rection with butylamine leading to N-(2,4,6-tri-t-butylbenzylidene)butylamine.Mechanism for the formation of these products is also discussed.
- Ishi, Akihiko,Okazaki, Renji,Inamoto, Naoki
-
p. 2529 - 2536
(2007/10/02)
-