87461-62-9Relevant academic research and scientific papers
Photocatalytic Reductive Formation of α-Tertiary Ethers from Ketals
Rossolini, Thomas,Ferko, Branislav,Dixon, Darren J.
supporting information, p. 6668 - 6673 (2019/09/03)
A general photocatalytic reductive strategy for the construction of unsymmetrical α-tertiary dialkyl ethers is reported. By merging Lewis acid-mediated ketal activation and visible-light photocatalytic reduction, in situ-generated α-alkoxy radicals were found to engage in addition reactions with a variety of olefinic partners. Good reaction efficiency is demonstrated with a range of ketals of aromatic and aliphatic ketones. Extension to acetal substrates is also described, demonstrating the overall synthetic utility of this methodology for complex ether synthesis.
Pd(II)-catalyzed conversion of styrene derivatives to acetals: Impact of (-)-sparteine on regioselectivity
Balija, Amy M.,Stowers, Kara J.,Schultz, Mitchell J.,Sigman, Matthew S.
, p. 1121 - 1124 (2007/10/03)
Pd[(-)-sparteine]Cl2 catalyzes the formation of dialkyl acetals from styrene derivatives with Markovnikov regioselectivity. The substrate scope of this reaction has been investigated, and initial mechanistic studies indicate that the reaction proceeds through an enol ether intermediate and a Pd-hydride.
Hemiacetals of Acetophenone. Aromatic Substituent Effects in the H+- and General-base-catalysed Decomposition in Aqueous Solution
McClelland, Robert A.,Engell, Karen M.,Larsen, Truels S.,Soerensen, Poul E.
, p. 2199 - 2206 (2007/10/02)
We describe a double-mixing stopped-flow technique for the study of the acid- and base-catalysed breakdown of the unstable methyl hemiacetals of aryl-substituted acetophenones in aqueous solution.The approach takes advantage of the build-up of the hemiacetal during the H+-catalysed decomposition of the corresponding dimethyl acetal.Thus, mixing a weakly basic solution of acetal with excess acid provides a solution containing unchanged acetal, the acetophenone product of the hydrolysis and the hemiacetal intermediate.After a short period of time ( +-catalysed acetal and hemiacetal breakdown are in good agreement with literature data, but our analysis suggests a larger resonance effect component than previously assumed.The corresponding set of Hammett plots for base catalysis of hemiacetal breakdown reveals a relatively weak dependence of the catalytic constants on aromatic substitution, which appears to be inconsistent with much stronger dependences on substitution in the leaving alcohol.We propose a case of non-perfect synchronization or imbalance in the transition state where, in the breakdown direction in a class n mechanism, the degree of C-O bond breakage as measured by β1g is considerable, but the change in hybridization of the central carbon (sp3 -> sp2), as measured by ρ, lags behind in the transition state so that there is less interaction with the aromatic substituents here.
