Reaction #317203

Reaction equation

5-bromoindan-1-one

4-tert-butylcyclohexyl amine

Sodium borohydride

→

(5-Bromo-2,3-dihydro-1H-inden-1-yl)(trans-4-tert-butylcyclohexyl)amine

Solvents

ethanol

Conditions

Workup

1. 1
   workup.STIRRINGthe resulting mixture was stirred for an additional 8 h at room temperature
2. 2
   OtherThe reaction was quenched
3. 3
   workup.ADDITIONby pouring into aqueous ammonia (2N, 300 mL)
4. 4
   FiltrationThe resulting inorganic precipitate was filtered off
5. 5
   Washwashed with dichloromethane (150 mL)
6. 6
   OtherThe organic layer was separated
7. 7
   Extractionthe remaining aqueous layer was extracted once with dichloromethane (150 mL)
8. 8
   DryingThe combined organic extracts were dried over Na2SO4
9. 9
   Filtrationfiltered
10. 10
    Concentrationconcentrated

Procedure

A mixture of 5-bromoindan-1-one (6.33 g, 30.0 mmol), titanium (IV) isopropoxide (17.8 mL, 60.0 mmol), 4-tert-butylcyclohexyl amine (9.32 g, 60.0 mmol) in absolute ethanol (200 mL) was stirred under nitrogen at room temperature for 12 h. Sodium borohydride (1.70 g, 45.0 mmol) was then added and the resulting mixture was stirred for an additional 8 h at room temperature. The reaction was quenched by pouring into aqueous ammonia (2N, 300 mL). The resulting inorganic precipitate was filtered off and washed with dichloromethane (150 mL). The organic layer was separated and the remaining aqueous layer was extracted once with dichloromethane (150 mL). The combined organic extracts were dried over Na2SO4, filtered and concentrated. Chromatography (10% to 20% EtOAc in Hexane) afforded (5-Bromo-2,3-dihydro-1H-inden-1-yl)(trans-4-tert-butylcyclohexyl)amine and the corresponding cis product (less polar). HPLC/MS: m/z=350.1 (M+1), Rt=3.01 min.

Source