- Synthesis of Carboxylic Acids by Palladium-Catalyzed Hydroxycarbonylation
-
The synthesis of carboxylic acids is of fundamental importance in the chemical industry and the corresponding products find numerous applications for polymers, cosmetics, pharmaceuticals, agrochemicals, and other manufactured chemicals. Although hydroxycarbonylations of olefins have been known for more than 60 years, currently known catalyst systems for this transformation do not fulfill industrial requirements, for example, stability. Presented herein for the first time is an aqueous-phase protocol that allows conversion of various olefins, including sterically hindered and demanding tetra-, tri-, and 1,1-disubstituted systems, as well as terminal alkenes, into the corresponding carboxylic acids in excellent yields. The outstanding stability of the catalyst system (26 recycling runs in 32 days without measurable loss of activity), is showcased in the preparation of an industrially relevant fatty acid. Key-to-success is the use of a built-in-base ligand under acidic aqueous conditions. This catalytic system is expected to provide a basis for new cost-competitive processes for the industrial production of carboxylic acids.
- Sang, Rui,Kucmierczyk, Peter,Dühren, Ricarda,Razzaq, Rauf,Dong, Kaiwu,Liu, Jie,Franke, Robert,Jackstell, Ralf,Beller, Matthias
-
supporting information
p. 14365 - 14373
(2019/09/06)
-
- Palladium-catalyzed selective generation of CO from formic acid for carbonylation of alkenes
-
A general and selective palladium-catalyzed alkoxycarbonylation of all kinds of alkenes with formic acid (HCOOH, FA) is described. Terminal, di-, tri-, and tetra-substituted including functionalized olefins are converted into linear esters with high yields and regioselectivity. Key-to-success is the use of specific palladium catalysts containing ligands with built-in base, e.g., L5. Comparison experiments demonstrate that the active catalyst system not only facilitates isomerization and carbonylation of alkenes but also promotes the selective decomposition of HCOOH to CO under mild conditions.
- Sang, Rui,Kucmierczyk, Peter,Dong, Kaiwu,Franke, Robert,Neumann, Helfried,Jackstell, Ralf,Beller, Matthias
-
supporting information
p. 5217 - 5223
(2018/04/24)
-
- Directed γ-C(sp3)-H Alkylation of Carboxylic Acid Derivatives through Visible Light Photoredox Catalysis
-
Visible light photoredox catalysis enables direct γ- C(sp3)-H alkylation of saturated aliphatic carbonyl compounds. Electron-deficient alkenes are used as the coupling partners in this reaction. Distinguished site selectivity is controlled by the predominant 1,5-hydrogen atom transfer of an amidyl radical generated in situ.
- Chen, Dian-Feng,Chu, John C. K.,Rovis, Tomislav
-
supporting information
p. 14897 - 14900
(2017/10/31)
-
- Highly stereoselective Lewis acid mediated conjugate radical additions to methyl α-D-glucopyranoside derivatives tethering an unsaturated ester moiety at C-4
-
The Lewis acid mediated conjugate additions of alkyl radicals to some 4- crotonyl derivatives of methyl α-D-glucopyranoside proceeded with a high level of diastereochemical induction to provide the adducts carrying a β- chiral butanoic ester.
- Munakata, Ryosuke,Totani, Kiichiro,Takao, Ken-Ichi,Tadano, Kin-Ichi
-
p. 979 - 982
(2007/10/03)
-