Sodium Hydroxide → 3-(3,4-Dichlorophenyl)-2-nortropene

To 1.08 g (4.03 mmol) 3-(3,4-dichloro-phenyl)-8-methyl-8-aza-bicyclo[3.2.1]oct-2-ene in 20 mL Cl(CH2)2Cl is added 1.31 mL (1.73 g, 12.08 mmol) of 1-chloroethyl chloroformate, and the resulting mixture is heated to reflux for 24 h. Evaporation of all volatiles gives an orange oil which is dissolved in methanol (20 mL) and heated to reflux for 1 h. Evaporation of all volatiles yielded an orange solid which is dissolved in 100 H2O and treated with 50 mL of 2.5 N NaOH. Extraction with 3×25 mL CH2Cl2, combining the organics and washing with 1×50 mL H2O, 1×50 mL brine, drying over MgSO4, filtering and evaporation a dark orange oil. Flash chromatography on SiO2 gel, eluting with EtOAc, then 10/1 EtOAc/2.0M NH3 in MeOH), gives 511 mg (2.01 mmol, a 50% yield) of the title compound as an orange solid. The oxalate salt of the title compound may be prepared by combining the title compound with 1 equiv. of oxalic acid in EtOH. A white solid precipitates. mp: 185-186° C. MS (ES) m/z 255 (MH)+.

1. temperaturethe resulting mixture is heated
2. temperatureto reflux for 24 h
3. customEvaporation of all volatiles
4. customgives an orange oil which
5. temperatureheated
6. temperatureto reflux for 1 h
7. customEvaporation of all volatiles
8. customyielded an orange solid which
9. extractionExtraction with 3×25 mL CH2Cl2
10. washwashing with 1×50 mL H2O, 1×50 mL brine
11. dry with materialdrying over MgSO4
12. filtrationfiltering
13. customevaporation a dark orange oil
14. washFlash chromatography on SiO2 gel, eluting with EtOAc
15. custom10/1 EtOAc/2.0M NH3 in MeOH), gives 511 mg (2.01 mmol

ORD record

ord-f269962702814b4298da136fb9eebb8b

Source dataset

uspto-grants-2003_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06632824B2