2-Mercaptobenzoic Acid → HCID 68865539, compound

To a solution of (2S,5R)-1-allyl-4-(3-chloro-propyl)-2,5-dimethyl-piperazine (14.05 g, 61 mmol) in anhydrous THF (78 mL) under argon was added thiosalicylic acid (10.33 g, 67 mmol, 1.1 eq) followed by the addition of a solution of tris(dibenzylidenacetone)-dipalladium (Pd2(dba)3, 2.8 g, 3.1 mmol, 5 mol %) and 1,4-bis(diphenylphosphino)butane (DPPB, 1.33 g, 3.1 mmol, 5 mol %) in anhydrous THF (26 mL, pre-mixed for 15 minutes). After stirring at room temperature for 2 hours, the mixture was filtered through Celite. The filtrate was concentrated in vacuo and the residue was partitioned between 1N aqueous HCl (70 mL) and Et2O (70 mL). The aqueous layer was separated and extracted with Et2O (50 mL×2), and treated with NaOH (solid) to bring its pH to 13. The aqueous phase was extracted with CHCl3 (50 mL×4). The combined organic phase was dried (Na2SO4) and concentrated in vacuo to give 11.6 g (100%) of (2S,5R)-4-(3-chloro-propyl)-2,5-dimethyl-piperazine as a light yellow oil.

1. filtrationthe mixture was filtered through Celite
2. concentrationThe filtrate was concentrated in vacuo
3. customthe residue was partitioned between 1N aqueous HCl (70 mL) and Et2O (70 mL)
4. customThe aqueous layer was separated
5. extractionextracted with Et2O (50 mL×2)
6. additiontreated with NaOH (solid)
7. extractionThe aqueous phase was extracted with CHCl3 (50 mL×4)
8. dry with materialThe combined organic phase was dried (Na2SO4)
9. concentrationconcentrated in vacuo

ORD record

ord-a8185eccfe9040e29b86a949975cd7d4

Source dataset

uspto-grants-2009_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07550467B2