Monomethyl terephthalate → HCID 67257206, compound

Participants

Reaction Steps

To a suspension of 4-(methoxycarbonyl)benzoic acid (11.35 g) in DCM (300 ml) are added 5 drops of DMF and the reaction mixture is stirred for 20 min at RT under a nitrogen atmosphere. To this suspension oxalyl chloride (5.67 ml) dissolved in DCM (60 ml) is slowly added at 0° C. (ice bath The ice bath is removed and the mixture is stirred for 4 h at RT. DCM (3×200 ml) is added to the reaction mixture and the volatiles are co-evaporated under reduced pressure (three times). Finally all volatiles are removed under vacuo to obtain an oil, which is dissolved in DCM (200 ml) and added dropwise to a solution of (3R,4R)-3-(3-ethoxy-4-methoxyphenyl)tetrahydro-2H-thiopyran-4-amine hydrochloride (18.23 g; compound C13) and DIPEA (41.1 ml) in DCM (200 ml) at 0° C. under nitrogen atmosphere. After stirring for 12 h at RT the reaction is quenched by addition of a saturated aqueous solution of sodium hydrogen carbonate. The organic phase is separated, dried over sodium sulfate, filtered and evaporated to dryness in vacuo. The resulting residue is suspended in DIP (300 ml) and heated under reflux for 3.5 h. The suspension is stirred for 2 d at RT and subsequently cooled to 0° (ice bath). The suspension is filtered and the filter cake is washed with little amounts of DIP and dried in vacuo for 12 h at 60° C. to give the title compound as a solid.

Provenance & Evidence