Reaktion #68977

Reaktionsgleichung

2-[4-(4,4,5,5-Tetramethyl[1,3,2]dioxaborolan-2-yl)phenoxy]pyridine

intermediate 1

3-trifluoromethanesulfonyloxy-8-azabicyclo[3.2.1]oct-2-ene-8-carboxylic acid tert-butyl ester

lithium chloride

K2CO3

3-trifluoromethanesulfonyloxy-8-azabicyclo[3.2.1]oct-2-ene-8-carboxylic acid tert-butyl ester

→

3-[4-(pyridin-2-yl-oxy)phenyl]-8-azabicyclo[3.2.1]oct-2-ene-8-carboxylic acid tert-butyl ester

Ausbeute 56.6%

Lösungsmittel

DME

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction medium is refluxed for 16 h
2. 2
   Trocknenthe organic phase is dried over MgSO4
3. 3
   Einengenconcentrated to dryness
4. 4
   SonstigeThe crude product obtained
5. 5
   Sonstigeis chromatographed on silica gel, elution

Vorschrift

2-[4-(4,4,5,5-Tetramethyl[1,3,2]dioxaborolan-2-yl)phenoxy]pyridine (0.62 g, 2.1 mmol), 3-trifluoromethanesulfonyloxy-8-azabicyclo[3.2.1]oct-2-ene-8-carboxylic acid tert-butyl ester (0.75 g, 2.1 mmol) (intermediate 1), tetrakis(triphenylphosphine)-palladium (0.24 g, 0.21 mmol) and lithium chloride (0.107 g, 2.52 mmol) are placed in 10 ml of DME and 2.6 ml of a 2N aqueous solution of K2CO3. The reaction medium is refluxed for 16 h. After hydrolysis and extraction with ethyl acetate, the organic phase is dried over MgSO4 and concentrated to dryness. The crude product obtained is chromatographed on silica gel, elution being carried out with a gradient of ethyl acetate in heptane ranging from 0% to 30%. 0.45 g of expected 3-[4-(pyridin-2-yl-oxy)phenyl]-8-azabicyclo[3.2.1]oct-2-ene-8-carboxylic acid tert-butyl ester is obtained.

Quelle