Reaktion #659466

Reaktionsgleichung

hydrogen chloride

5-(4-Methyl-5-trifluoromethyl-isoxazol-3-yl)-thiophene-2-carboxylic acid

N-Boc-piperazine

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product

Ausbeute 69.0%

[5-(4-Methyl-5-trifluoromethyl-isoxazol-3-yl)-thiophen-2-yl]-pipe razin-1-yl-methanone, hydrochloride

Ausbeute 69.0%

Lösungsmittel

1,4-dioxane

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction mixture was evaporated to a solid
2. 2
   Sonstigetriturated
3. 3
   Filtrationfiltered with the aid of water
4. 4
   Waschenwashed with a 1 N aqueous hydrochloric acid solution
5. 5
   Sonstigedried
6. 6
   Sonstigethen chromatographed on silica gel with EtOAc/hexanes (50%) as eluant
7. 7
   Sonstigeto afford intermediate N-Boc protected product as a colorless solid (165 mg, 74%)
8. 8
   Sonstigeafter which time the reaction mixture was evaporated to approximately ½ volume
9. 9
   workup.ADDITIONdiluted with ethyl ether (20 mL)
10. 10
    FiltrationThe resulting solids were filtered
11. 11
    Sonstigeair dried

Vorschrift

Prepared from 5-(4-Methyl-5-trifluoromethyl-isoxazol-3-yl)-thiophene-2-carboxylic acid and N-Boc-piperazine by the method described in Example 2 Method B. The reaction mixture was evaporated to a solid, triturated and filtered with the aid of water, then washed with a 1 N aqueous hydrochloric acid solution followed by water. The solid was air dried then chromatographed on silica gel with EtOAc/hexanes (50%) as eluant to afford intermediate N-Boc protected product as a colorless solid (165 mg, 74%). The Boc-protected intermediate was dissolved in 1,4-dioxane (5 mL) and treated with a 4 N solution of hydrogen chloride in 1,4-dioxane and stirred for 12 hr, after which time the reaction mixture was evaporated to approximately ½ volume and diluted with ethyl ether (20 mL). The resulting solids were filtered and air dried to afford product as a colorless solid (131 mg, 69% overall). 1H NMR (D2O) 2.16 (s, 3H), 3.22 (m, 4H), 3.87 (m, 4H), 7.34 (d, J=4.0, 1H), 7.42 (d, J=4.0, 1H). 19F NMR −63.6. LC/MS 4.34 min, [M+1]+ 346.

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