94417-52-4Relevant academic research and scientific papers
Lewis Acid Activated Reactions of Mixed (O,Se) Acetals with Allyltrimethylsilane and Allyltributylstannane
Hermans, Bernard,Hevesi, Laszlo
, p. 6141 - 6147 (2007/10/03)
On the basis of preferential complexation of oxygen or selenium atoms by different Lewis acids, it was expected that, depending on the Lewis acid employed, the title reactions would lead to selective formation of homoallyl ethers or homoallyl selenides.This has not been confirmed by experiment: in almost all the reactions tried homoallyl ethers largely predominated, or were the exclusive allylation products, even when strongly oxygenophilic Lewis acids such as TiCl4 were used.In the cases of the latter type of Lewis acids, the results observed with (O,Se) and a couple of (O, S) mixed acetals are interpreted in terms of two major factors operating in opposite directions. 1H NMR data of a mixture of TiCl4 and (O,Se) acetal indicate that preferential (but not exclusive) complexation of the oxygen moiety takes place indeed.However, because of the much stronger C-O bond as compared to the C-Se bond, this latter (also activated by the Lewis acid to some extent) undergoes cleavage by allyl metals to give homoallyl ethers as predominating products.In contrast with BF3*OEt2, boron trichloride and boron tribromide were found to react with (O, Se) acetals to give the corresponding α-halo selenides, which in turn were cleanly transformed into homoallyl selenides on reaction with allyltrimethylsilane in the presence of tin tetrachloride.
C/Se bond cleavage of functionalized selenides by lithium arenides: Application to the geminal di-allylation of the carbonyl group of aldehydes and ketones
Krief,Nazih
, p. 8115 - 8118 (2007/10/02)
Selenoacetals as well as mixed (O,Se) acetals react with lithium arenides and produce, besides lithium selenolates, α-selenoalkyllithiums or α-alkoxyalkyllithiums respectively. We took advantage of these reactions as well as of the ones involving the synthesis of alkyllithiums from selenides to propose an original method for geminal di-allylation of the carbonyl group of aldehydes and ketones.
Regioselective syntheses of polycyclic compounds by carbanion-mediated polycyclisation of olefins
Krief,Barbeaux
, p. 417 - 420 (2007/10/02)
This paper reports straightforward syntheses of 1-aryl-bicyclo-[n. 1.0]-alkanes, 1-aryl-bicyclo-[3.3.0]-alkanes and of 1-phenyl-1,4-dimethyl-cyclopentane from unsaturated benzylselenides which involve the organolithiums-mediated cyclisation of olefins and
A NOVEL METHOD FOR THE GEMINAL DIALKYLATION OF THE CARBONYL GROUP OF AROMATIC ALDEHYDES AND KETONES
Clarembeau, M.,Krief, A.
, p. 1719 - 1722 (2007/10/02)
The title transformation is efficiently achieved by using the selenium methodology which involves the sequential reductive alkylation of arylselenoacetals and of benzylselenides.
METALLATION OF BENZYL SELENIDES AND OF α-ARYL SELENOACETALS. SCOPE AND LIMITATIONS.
Clarembeau, M.,Krief, A.
, p. 1723 - 1726 (2007/10/02)
α-Metallo benzylselenides and α-metallo selenoacetals derived from aromatic aldehydes have been conveniently prepared by metallation of the corresponding carbon acids.KDA in THF proved among the various basic systems tested, the most efficient.
SYNTHESIS OF SELENOACETALS
Clarembeau, M.,Cravador, A.,Dumont, W.,Hevesi, L,Krief, A.,et al.
, p. 4793 - 4812 (2007/10/02)
This paper reports our results concerning the syntheses of various bis(alkylseleno)alkanes and some of their arylseleno analogues by different methods.The scope and limitation of each of them are presented.
