59671-36-2Relevant academic research and scientific papers
Intermolecular C-O Bond Formation with Alkoxyl Radicals: Photoredox-Catalyzed α-Alkoxylation of Carbonyl Compounds
Banoun, Camille,Bourdreux, Flavien,Magnier, Emmanuel,Dagousset, Guillaume
supporting information, p. 8926 - 8930 (2021/11/17)
Due to the high reactivity of alkoxyl (RO·) radicals and their propensity to easily undergo β-scission or Hydrogen Atom Transfer (HAT) reactions, intermolecular alkoxylations involving RO· radicals are barely described. We report herein for the first time the efficient intermolecular trapping of alkoxyl radicals by silyl enol ethers. This photoredox-mediated protocol enables the introduction of both structurally simple and more complex alkoxy groups into a wide range of ketones and amides.
Tandem Acid/Pd-Catalyzed Reductive Rearrangement of Glycol Derivatives
Ciszek, Benjamin,Fleischer, Ivana,Kathe, Prasad,Schmidt, Tanno A.
supporting information, p. 3641 - 3646 (2020/03/25)
Herein, we describe the acid/Pd-tandem-catalyzed transformation of glycol derivatives into terminal formic esters. Mechanistic investigations show that the substrate undergoes rearrangement to an aldehyde under [1,2] hydrogen migration and cleavage of an oxygen-based leaving group. The leaving group is trapped as its formic ester, and the aldehyde is reduced and subsequently esterified to a formate. Whereas the rearrangement to the aldehyde is catalyzed by sulfonic acids, the reduction step requires a unique catalyst system comprising a PdII or Pd0 precursor in loadings as low as 0.75 mol % and α,α′-bis(di-tert-butylphosphino)-o-xylene as ligand. The reduction step makes use of formic acid as an easy-to-handle transfer reductant. The substrate scope of the transformation encompasses both aromatic and aliphatic substrates and a variety of leaving groups.
Aliphatic C?C Bond Cleavage in α-Hydroxy Ketones by a Dioxygen-Derived Nucleophilic Iron–Oxygen Oxidant
Bhattacharya, Shrabanti,Rahaman, Rubina,Chatterjee, Sayanti,Paine, Tapan K.
supporting information, p. 3815 - 3818 (2017/03/27)
A nucleophilic iron–oxygen oxidant, formed in situ in the reaction between an iron(II)–benzilate complex and O2, oxidatively cleaves the aliphatic C?C bonds of α-hydroxy ketones. In the cleavage reaction, α-hydroxy ketones without any α-C?H bond afford a 1:1 mixture of carboxylic acid and ketone. Isotope labeling studies established that one of the oxygen atoms from dioxygen is incorporated into the carboxylic acid product. Furthermore, the iron(II) complex cleaves an aliphatic C?C bond of 17-α-hydroxyprogesterone affording androstenedione and acetic acid. The O2-dependent aliphatic C?C bond cleavage of α-hydroxy ketones containing no α-C?H bond bears similarity to the lyase activity of the heme enzyme, cytochrome P450 17A1 (CYP17A1).
Simple phase transfer catalytic method for α-methoxylation of sterically hindered ketones
Abele,Rubina,Shymanska,Lukevics
, p. 1371 - 1376 (2007/10/02)
Reactions of sterically hindered ketones of ArylCOCHR1R2 type (R1, R2 = Me, Et, Ph) with carbon tetrachloride and methyl iodide in the presence of solid KOH and 18-crown-6 afford the corresponding α-methoxyketones [ArylCOC(OMe)R1R2] in one-pot process in 30-67% yields.
Silver ion induced reactions of α-haloimines
De Kimpe, Norbert,Stevens, Christian
, p. 6753 - 6770 (2007/10/02)
The silver ion induced reactions of α-haloimines are markedly different from similar reactions with the corresponding α-haloketones. The various reactions of α-haloimines, including α-alkoxylation 1,2-dehydrohalogenation, rearrangement via α-alkoxyaziridines, Favorskii-rearrangement and Wagner Meerwein rearrangement, are compared and evaluated with silver-induced reactions of α-haloketones The silver ion assisted reactions of α-haloimines are best interpreted in terms of the intermediacy c α-imidoylcarbenium ions or pseudo-α-imidoylcarbenium ions.
