6270-03-7Relevant articles and documents
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.
PREPARATION OF DIESTERS OF (METH)ACRYLIC ACID FROM EPOXIDES
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Page/Page column 23, (2020/03/05)
The application relates to a process for preparing a (meth)acrylic acid diester by reacting a (meth)acrylic acid anhydride with an epoxide in the presence of a catalyst system comprising a first and/or second catalyst in combination with a co-catalyst. The first catalyst is a halide of Mg or a trifluoromethanesulfonate of a rare earth element; the second catalyst is a Cr(lll) salt; and the co- catalyst is a tertiary amine, a quaternary ammonium salt, a tertiary phosphine or a quaternary phosphonium salt.
SYNTHESIS OF HYPERVALENT IODINE REAGENTS WITH DIOXYGEN
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Paragraph 0187-0188, (2019/01/15)
Methods of synthesis of hypervalent iodine reagents and methods for oxidation of organic compounds are disclosed.