Réaction #1102170

Équation de réaction

1-methyl-3,4-dihydroisoquinoline

→

(R)-1-Methyl-1,2,3,4-tetrahydroisoquinoline

Rendement 82.0%

Solvants

dichloromethane

dichloromethane

Conditions de réaction

Traitement

1. 1
   Températureto warm to −10° C. over 1 h
2. 2
   AutreThe solvent is removed in vacuo
3. 3
   workup.DISSOLUTIONthe residue is dissolved in methanol (10 mL)
4. 4
   TempératureAfter cooling to 0° C.
5. 5
   workup.ADDITIONAmberlyst 15 (1 g) is added
6. 6
   FiltrationThe resin is filtered off
7. 7
   Lavagewashed with dichloromethane and methanol
8. 8
   workup.ADDITIONsolution of ammonia in methanol (2M, 3 mL) is added
9. 9
   workup.STIRRINGthe mixture is shaken overnight
10. 10
    Filtrationfiltered
11. 11
    AutreThe filtrate is evaporated in vacuo

Mode opératoire

To a cooled (−35° C.) solution of reducing agent 9 (526 mg, (0.78 mmol) in dichloromethane (3 mL) is added solution of 1-methyl-3,4-dihydroisoquinoline (32 mg, 0.22 mmol) in dichloromethane (3 mL) dropwise over 15 min. The mixture is allowed to warm to −10° C. over 1 h and then kept at 0° C. for 4 h. The solvent is removed in vacuo and the residue is dissolved in methanol (10 mL). After cooling to 0° C., Amberlyst 15 (1 g) is added and the mixture is shaken for 1 h at room temperature. The resin is filtered off and washed with dichloromethane and methanol, then solution of ammonia in methanol (2M, 3 mL) is added and the mixture is shaken overnight, then filtered. The filtrate is evaporated in vacuo to give (R)-1-Methyl-1,2,3,4-tetrahydroisoquinoline (26 mg, 82%, e.e.=74%, determined by chiral HPLC).

Source