US 12,103,918 B2
Synthesis of chromanol derivatives
Melanie Weingarten, Ludwigshafen am Rhein (DE); Wolfgang Siegel, Ludwigshafen am Rhein (DE); and Michael Puhl, Ludwigshafen am Rhein (DE)
Assigned to BASF SE, Ludwigshafen am Rhein (DE)
Appl. No. 17/268,981
Filed by BASF SE, Ludwigshafen am Rhein (DE)
PCT Filed Aug. 16, 2019, PCT No. PCT/EP2019/072029
§ 371(c)(1), (2) Date Feb. 17, 2021,
PCT Pub. No. WO2020/035600, PCT Pub. Date Feb. 20, 2020.
Claims priority of application No. 18189589 (EP), filed on Aug. 17, 2018.
Prior Publication US 2021/0309626 A1, Oct. 7, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C07D 311/58 (2006.01); B01J 21/16 (2006.01); B01J 37/06 (2006.01)
CPC C07D 311/58 (2013.01) [B01J 21/16 (2013.01); B01J 37/06 (2013.01)] 18 Claims
 
1. Process for preparing a compound of the general formula I

OG Complex Work Unit Chemistry
wherein
R1, R2 and R3 independently of each other are selected from hydrogen and methyl,
R4 is selected from hydrogen and C1-C6-alkanoyl, and
X is selected from C1-C20-alkyl and C2-C20-alkenyl,
comprising the following steps:
a) providing a quinone compound of the general formula II,

OG Complex Work Unit Chemistry
wherein R1, R2 and R3 are as defined above,
b) catalytic hydrogenation of the quinone compound of formula II provided in step a) in the presence of hydrogen, a hydrogenation catalyst and in the presence of a carbonate solvent to obtain a hydroquinone compound of the general formula III,

OG Complex Work Unit Chemistry
wherein R1, R2 and R3 are as defined above,
c) reacting the hydroquinone compound III provided in step b) with an unsaturated compound of the general formula IV.a or IV.b

OG Complex Work Unit Chemistry
wherein
X is as defined above,
Y is selected from OH, halogen, —O—R11, —S—R12 and —SO2—R12,
R11 is selected from C1-C4-alkyl, C1-C4-alkanoyl and trifluoroacetyl, and
R12 is selected from C1-C6-alkyl, trifluoromethyl and phenyl, where phenyl is unsubstituted or substituted with 1, 2, 3, 4 or 5 radicals selected from halogen and methyl,
in the presence of a condensation catalyst, and
d) in case R4 is selected from C1-C6-alkanoyl, reacting the condensation product obtained in step c) with a C2-C7-carboxylic acid or with a C2-C7-carboxylic acid anhydride in the presence of an esterification catalyst,
or reacting the condensation product obtained in step c) with an activated C2-C7-carboxylic acid in the presence of a base.