84896-21-9Relevant academic research and scientific papers
Mukaiyama aldol and Michael reactions catalyzed by lanthanide iodides
Giuseppone, Nicolas,Van De Weghe, Pierre V.,Mellah, Mohamed,Collin, Jacqueline
, p. 13129 - 13148 (1998)
Samarium diiodide is an efficient catalyst precursor which allows the formation of condensation products between various carbonyl compounds and ketene silyl acetals or enoxysilanes. With α,β-unsaturated carbonyl compounds, 1,2- or 1,4-additions are observed according to the structure of the substrate. α,β-Unsaturated ketones yield to enoxysilanes by selective Michael additions. Aldol products are isolated as silyl ethers. The mechanisms of the reactions are discussed.
Yb(OTf)3-TMSCl, a novel catalytic system in cross-aldol reactions
Kagawa, Natsuko,Toyota, Masahiro,Ihara, Masataka
, p. 655 - 657 (2007/10/03)
A combination of Yb(OTf)3 and TMSCl influenced the outcome of cross-aldol reactions of cycloalkanones and benzaldehyde. Interestingly, reaction of cycloheptanone and cyclooctanone with aldehydes under the Yb(OTf)3- TMSCl reagent system provides 3-(2-oxocycloalkyl)-3- phenylpropanals in conjunction with the corresponding aldol products.
Diiodosamarium, an excellent catalyst precursor for Aldolisation and Michael Reactions.
Weghe, Pierre Van de,Collin, Jacqueline
, p. 3881 - 3884 (2007/10/02)
SmI2 is the precursor of efficient catalysts for the aldolisation reactions of aldehydes and ketones with enol silanes, α,β-unsaturated ketones give 1,4-additions selectively.Key Words: Samarium diiodide; aldolisation reactions; Michael additions; ketene
Fluoride Ion Catalyzed Aldol Reaction between Enol Silyl Ethers and Carbonyl Compounds
Nakamura, Eiichi,Shimizu, Makoto,Kuwajima, Isao,Sakata, J.,Yokoyama, K.,Noyori, R.
, p. 932 - 945 (2007/10/02)
A new aldol reaction effected by the reaction of enol trimethylsilyl ethers and a quarternary ammonium fluoride is reported.Under the influence of a catalytic amount of tetrabutylammonium fluoride at low temperatures, enol silyl ethers react with various aldehydes to give the corresponding aldol trimethylsilyl ethers in fair to good yields.The silyl group of these products can be smoothly removed under mild conditions.Ketones, epoxides, and esters do not serve as electrophiles in this reaction.The reaction proceeds in a regiospecific manner with respect to the enol silyl ethers; the reactions of two regioisomers of 2-methylcyclohexanone with benzaldehyde cleanly give the respective regioisomeric aldol products.The reaction of 4-tert-butyl-1-methyl-2-(trimethylsiloxy)cyclohexene proceeds exclusively by the axial attack of the electrophile, making a strong contrast with the related cases reported on this cyclohexanone system.The aldol addition of a ketone and an aldehyde can be performed without the isolation of the enol silyl ether of the ketone by effecting both the silylation of the ketone and the aldol reaction with the aid of a fluoride anion.The characteristic behavior of the enolate species in this reaction can be rationalized by considering a mobile equilibrium in which the combination of fluorotrimethylsilane and a quarternary ammonium enolate functions as key controlling factor.
