Reaktion #48911

Reaktionsgleichung

3,4,5-trichloropyridine

KH2PO4

Sodium hydride

4-amino-8-(cyclopropylmethoxy)-3-ethyl-7-methoxy-2H-chromen-2-one

sodium hydride

3,4,5-trichloropyridine

→

8-(cyclopropylmethoxy)-4-(3,5-dichloropyridin-4-ylamino)-3-ethyl-7-methoxy-2H-chromen-2-one

Lösungsmittel

DMSO

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter 2 h
2. 2
   workup.WAITAfter an additional 2 h at 60° C.
3. 3
   Extraktionextracted with ethyl acetate (40 mL×2)
4. 4
   SonstigeThe combined extracts were dried
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated
7. 7
   Sonstigepurified by silica gel chromatography (7:3→1:4; hexanes:ethyl acetate)

Vorschrift

Sodium hydride (8 mg, 60%, 0.2 mmol) was added to a solution of 4-amino-8-(cyclopropylmethoxy)-3-ethyl-7-methoxy-2H-chromen-2-one (24 mg, 0.083 mmol) and DMSO (3 mL) at rt under N2. After 5 min. 3,4,5-trichloropyridine (19 mg, 0.1 mmol) was added, and the reaction was heated at 60° C. After 2 h, more 3,4,5-trichloropyridine (25 mg, 0.14 mmol) was added followed by more sodium hydride (15 mg, 60%, 0.38 mmol). After an additional 2 h at 60° C., the reaction was poured into 1M KH2PO4 (40 mL) and extracted with ethyl acetate (40 mL×2). The combined extracts were dried, filtered, concentrated, and purified by silica gel chromatography (7:3→1:4; hexanes:ethyl acetate) to give 8-(cyclopropylmethoxy)-4-(3,5-dichloropyridin-4-ylamino)-3-ethyl-7-methoxy-2H-chromen-2-one: MS (ESI): 434.8.

Quelle