US 12,006,287 B2
Process for alkoxycarbonylation of ethylenically unsaturated compounds using benzene-based diphosphine ligands and aluminium triflate
Peter Kucmierczyk, Herne (DE); Ricarda Dühren, Rostock (DE); Dirk Fridag, Haltern am See (DE); Johannes Knossalla, Gahlen (DE); Anna Chiara Sale, Recklinghausen (DE); Ana Markovic, Haltern am See (DE); Alexander Brächer, Haltern am See (DE); Matthias Beller, Ostseebad Nienhagen (DE); and Robert Franke, Marl (DE)
Assigned to EVONIK OXENO GMBH & CO. KG, Marl (DE)
Filed by EVONIK OPERATIONS GMBH, Essen (DE)
Filed on Nov. 19, 2021, as Appl. No. 17/530,720.
Claims priority of application No. 20209477 (EP), filed on Nov. 24, 2020.
Prior Publication US 2022/0162150 A1, May 26, 2022
Int. Cl. C07C 67/38 (2006.01); B01J 31/02 (2006.01); B01J 31/22 (2006.01)
CPC C07C 67/38 (2013.01) [B01J 31/0267 (2013.01); B01J 31/2239 (2013.01); B01J 2531/0208 (2013.01); B01J 2531/824 (2013.01)] 9 Claims
 
1. Process comprising the process steps of:
a) initially charging an ethylenically unsaturated compound,
b) adding a ligand of formula (I):

OG Complex Work Unit Chemistry
where
R1 and R3 are each a —(C3-C20)-heteroaryl radical,
R2 and R4 are each —(C1-C12)-alkyl,
and a compound comprising Pd;
c) pretreating aluminium triflate at least twice by applying a vacuum to reduce pressure and the vacuum applied is broken by flooding with inert gas;
d) adding the pretreated aluminium triflate from c) as a solution, where the ratio of aluminium triflate:ligand is in the range from 2.5 mol:1 mol to 15 mol:1 mol;
e) adding an alcohol;
f) feeding in CO;
g) heating the reaction mixture from a) to f), with conversion of the ethylenically unsaturated compound to an ester.