反应详情

温度

65 °C

In a dry Schlenk tube under argon was placed (R,R)-Ethylene-1,2-bis(η5 -4,5,6,7-tetrahydroindenyl) titanium (R)-1,1'-binaphth-2,2'-diolate (25 mg, 0.042 mmol) and THF (4 mL). A solution of n-butyllithium (53 μL, 0.084 mmol, 1.6M in hexane) was added and the mixture was stirred for 10 minutes, at which time the color was a dark shade of brown. Phenylsilane (13 μL, 0.105 mmol) was then added and the mixture was stirred for another 10 minutes, the color changing to a darker shade of brown. Acetophenone N-benzyl imine (87 mg, 0.42 mmol) was then added and the reaction vessel was sealed and moved to a dry box. The reaction mixture was transferred to a Parr high pressure reactor, which was sealed and removed from the dry box. The reactor was charged with hydrogen to 1900 psi and heated to 65° C. After stirring for 48 hours the mixture was opened to air and concentrated. The residue was diluted with diethyl ether (20 mL) and extracted with 1N HCl (3×10 mL). The combined aqueous layers were basified with NaOH until strongly basic to pH paper and extracted with diethyl ether (4×25 mL). The organic layers were combined, dried over sodium sulfate and concentrated to produce 82-89% yield of N-benzyl-1-phenylethylamine. The enantiomeric excess (ee), as determined by HPLC analysis of the free amine using a Chiralcel OD column, was 89-92% in favor of the (R)enantiomer.

1. customIn a dry Schlenk tube under argon was placed
2. stirringthe mixture was stirred for another 10 minutes
3. customthe reaction vessel was sealed
4. custommoved to a dry box
5. customwas sealed
6. customremoved from the dry box
7. additionThe reactor was charged with hydrogen to 1900 psi
8. stirringAfter stirring for 48 hours the mixture
9. concentrationconcentrated
10. additionThe residue was diluted with diethyl ether (20 mL)
11. extractionextracted with 1N HCl (3×10 mL)
12. extractionextracted with diethyl ether (4×25 mL)
13. dry with materialdried over sodium sulfate
14. concentrationconcentrated