Reaktion #626042

Reaktionsgleichung

4-bromo-2-(cyclohexylmethyl)-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

THF

NaBH4

→

title product

Ausbeute 93.0%

4-Bromo-6-(cyclohexylmethyl)-1,2,3,5-tetrahydro-s-indacene

Ausbeute 93.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe resulting mixture was stirred for 12 h at room temperature
2. 2
   Sonstigeevaporated to a volume of ca. 300 ml
3. 3
   workup.ADDITION100 ml of 3.0 M HCl was added
4. 4
   ExtraktionThe product was extracted with 3×200 ml of dichloromethane
5. 5
   ExtraktionThe organic extract
6. 6
   Trocknenwas dried over Na2SO4
7. 7
   Sonstigeevaporated to dryness
8. 8
   TemperaturA solution of the residue and 1.4 g of TsOH in 800 ml of toluene was refluxed for 30 min with Dean-Stark head
9. 9
   Sonstigethe filtrate was evaporated to dryness

Vorschrift

To a solution of 39.5 g (0.114 mol) of 4-bromo-2-(cyclohexylmethyl)-3,5,6,7-tetrahydro-s-indacen-1(2H)-one in 170 ml of THF 15.2 g (0.398 mol) of NaBH4 was added. Further on, 340 ml of methanol was added dropwise by vigorous stirring for 2 h. The resulting mixture was stirred for 12 h at room temperature, evaporated to a volume of ca. 300 ml, and then 100 ml of 3.0 M HCl was added. The product was extracted with 3×200 ml of dichloromethane. The organic extract was dried over Na2SO4 and then evaporated to dryness. A solution of the residue and 1.4 g of TsOH in 800 ml of toluene was refluxed for 30 min with Dean-Stark head. The obtained solution was passed through short layer (50 mm) of silica gel 60 (40-63 um), the filtrate was evaporated to dryness. This procedure gave 34.7 g (93%) of the title product which was further used without an additional purification.

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