352431-93-7Relevant academic research and scientific papers
One-pot enol silane formation-Mukaiyama aldol reactions: Crossed aldehyde-aldehyde coupling, thioester substrates, and reactions in ester solvents
Downey, C. Wade,Dixon, Grant J.,Ingersoll, Jared A.,Fuller, Claire N.,MacCormac, Kenneth W.,Takashima, Anna,Sediqui, Rohina
supporting information, (2019/10/14)
Trimethylsilyl trifluoromethanesulfonate (TMSOTf) and a trialkylamine base promote both in situ enol silane/silyl ketene acetal formation and Mukaiyama aldol addition reactions between a variety of reaction partners in a single reaction flask. Isolation of the required enol silane or silyl ketene acetal is not necessary. For example, crossed aldol reactions between α-disubstituted aldehydes and non-enolizable aldehydes yield β-hydroxy aldehydes in good yield. In a related reaction, the common laboratory solvent ethyl acetate functions as both an enolate precursor and a green reaction solvent. When thioesters are employed as enolate precursors, high yields for additions to non-enolizable aldehydes are routinely observed.
The Mukaiyama aldol and Mukaiyama-Michael reactions promoted by commercially available molecular sieves
Anada, Masahiro,Washio, Takuya,Watanabe, Yudai,Hashimoto, Shunichi
experimental part, p. 1489 - 1503 (2010/10/20)
The Mukaiyama aldol reaction of silyl ketene acetals with aldehydes has been effected by using commercially available 4 molecular sieves (4 MS) as a promoter. Various silyl ketene acetals and silyl enol ethers have been shown to be effective nucleophiles
Stereocontrol in a one-pot procedure for anionic oxy-Cope rearrangement followed by intramolecular aldol reaction
Rutherford, Alistair P.,Gibb, Cameron S.,Hartley, Richard C.,Goodman, Jonathan M.
, p. 1051 - 1061 (2007/10/03)
Racemic β-hydroxycyclohexanones with up to three chiral centres have been synthesized in a stereocontrolled way using the novel anionic oxy-Cope (AOC) rearrangement of acyclic enol ethers. The first examples of compounds containing an aldehyde and an enol ether in a 1,5 relationship are reported. Stereocontrol in the cyclisation of these compounds by a 6-(enolendo)-exo-trig intramolecular aldol reaction has been studied: there is high stereoselectivity for an axial hydroxy group in the product β-hydroxycyclohexanones. AM1 calculations show that there is a stabilising electrostatic attraction between the oxygen atom of the axial C-3 hydroxy group and the electron-poor carbon at C-1 in the intermediate oxonium ions. ≥87% of AOC rearrangement occurs via a chair-like transition state giving rise to the 5,6-anti stereochemistry of the β-hydroxycyclohexanones. Trapping the enolate product of AOC rearrangement with oxygen gives fragmentation via a 1,2-dioxetane.
Stereoselective synthesis of β-hydroxycyclohexanones
Rutherford, Alistair P.,Gibb, Cameron S.,Hartley, Richard C.
, p. 685 - 688 (2007/10/03)
We have developed a stereoselective route to β-hydroxycyclohexanones using the aldol reaction, the Takai alkylidenation, a novel anionic oxy-Cope rearrangement of acyclic enol ethers and an intramolecular aldol reaction. The stereoselectivity of the acid-induced, 6-(enolendo)-exo-trig, intramolecular, aldol reaction between an aldehyde and an enol ether has been investigated. The strong preference for an axial hydroxyl in the β-hydroxycyclohexanone products is explained in terms of an electrostatic interaction in the oxonium ion intermediate.
