p-Toluenesulfonic acid → HCID 53664316, compound

To a stirred suspension of 4-nitrobenzyltriphenylphosphonium chloride (10.02 g, 23.1 mmol) in CH2Cl2 (100 mL) was added 4-methylmorpholine (2.54 mL, 23.1 mmol) was added. When all the solid had dissolved, Boc-HphH (4.04 g, 15.4 mmol) was added. After 24 hrs., the reaction mixture was diluted with CH2Cl2 (200 mL), and filtered. The filtrate was washed with 1M HCl (200 mL) saturated aqueous sodium bicarbonate (200 mL); dried over MgSO4, filtered and concentrated under reduced pressure, giving 4.00 g of crude intermediate, a portion of which was purified by chromatography (gradient elution: 10-30% ethyl acetate/hexane) to permit NMR analysis of the intermediate, (S)-t-butoxycarbonyl-3-amino-1-(4-nitrophenyl)-5-phenyl-1-pentene. TLC: (30% EtOAc /hexane) Rf =0.49. To a solution of this material (2.76 g, 7.2 mmol) in Et2O (25 mL), was added a solution of anhydrous p-toluenesulfonic acid (2.76 g, 16.0 mmol) in Et2O (10 mL). The reaction was left to stir 16 hrs, filtered; washed solid with Et2O (25 mL), and dried in vacuo, giving 2 g (61%) of (S)-3-amino-1-(4-nitrophenyl)-5-phenyl-1-pentene as a single spot on TLC: (Rf=0.49, 10% MeOH/CH2Cl2).

1. additionwas added
2. dissolutionWhen all the solid had dissolved
3. additionBoc-HphH (4.04 g, 15.4 mmol) was added
4. filtrationfiltered
5. washThe filtrate was washed with 1M HCl (200 mL) saturated aqueous sodium bicarbonate (200 mL)
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customgiving 4.00 g of crude intermediate
10. customa portion of which was purified by chromatography (gradient elution: 10-30% ethyl acetate/hexane)
11. waitThe reaction was left
12. filtrationfiltered
13. washwashed solid with Et2O (25 mL)
14. customdried in vacuo

ORD record

ord-e158c4f7f9bd483f9aafe3bf088e7fe3

Source dataset

uspto-grants-1998_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05776718