Reaktion #2152223

Reaktionsgleichung

K2CO3

N2

methanesulfonic acid 4-(2-methyl-[1,3]dioxolan-2-yl)-thiazol-2-ylmethyl ester

5-nitro-1H-pyrazole

bromide

→

title compound

4-(2-Methyl-[1,3]dioxolan-2-yl)-2-(3-nitro-pyrazol-1-ylmethyl)-thiazole

Lösungsmittel

acetone

acetone

EA

Water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added
2. 2
   ExtraktionThe aq. layer was extracted with EA (10 mL)
3. 3
   Trocknenextracts were dried over MgSO4
4. 4
   Filtrationfiltered
5. 5
   Sonstigethe solvents were removed under reduced pressure
6. 6
   SonstigePurification of the residue by FC (2:1 hept-EA)

Vorschrift

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of methanesulfonic acid 4-(2-methyl-[1,3]dioxolan-2-yl)-thiazol-2-ylmethyl ester (320 mg, 1.15 mmol) in acetone (6.0 mL) was added to a solution of 5-nitro-1H-pyrazole (136 mg, 1.20 mmol) in acetone (6.0 mL). K2CO3 (800 mg, 5.73 mmol) followed by TBA bromide (741 mg, 0.23 mmol) were added and the reaction mixture was stirred at rt overnight. Water (10 mL) and EA (10 mL) were added. The aq. layer was extracted with EA (10 mL) and the combined org. extracts were dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (2:1 hept-EA) gave the title compound as a yellow oil. TLC: rf (2:1 hept-EA)=0.10. LC-MS-conditions 01: tR=0.81 min, [M+H]+=296.90.

Quelle