Réaction #4561

Équation de réaction

n-butyllithium

2-(4-(4-bromo-2-fluorophenoxy)phenoxy)propanaldehyde

diisopropylamine

ethyl acetate

NH4Cl

→

product

Rendement 70.0%

4-(4-(4-Bromo-2-fluorophenoxy)phenoxy)-3-hydroxypentanoate ethyl ester

Rendement 70.0%

Solvants

hexane

ether

ether

ether

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONwas slowly added
2. 2
   Autrethe aqueous phase separated
3. 3
   Extractionextracted with ether
4. 4
   SéchageThe combined organic layers were dried over MgSO4
5. 5
   Autreevaporated to dryness
6. 6
   Autrethe residue purified by prep LC
7. 7
   Lavageeluting with 85:15 hexane
8. 8
   AutreThe resulting colorless oil was thoroughly dried

Mode opératoire

A solution of 1.54 ml (11 mmol) of diisopropylamine in 20 ml of ether was cooled under N2 to -78° C. and 6.9 ml (11 mmol) of 1.6M n-butyllithium in hexane was slowly added. After 15 min of -78° C. 0.97 g (11 mmol) of ethyl acetate in 3 ml of ether was added dropwise. The resulting mixture was stirred at -78° C. for 15 min when a solution of 3.39 g (10 mmol) of 2-(4-(4-bromo-2-fluorophenoxy)phenoxy)propanaldehyde in 5 ml of ether was slowly added. The mixture was allowed to warm to room temperature, poured into aqueous NH4Cl and the aqueous phase separated and extracted with ether. The combined organic layers were dried over MgSO4 and evaporated to dryness and the residue purified by prep LC, eluting with 85:15 hexane:acetone. The resulting colorless oil was thoroughly dried to leave 2.99 g of product. Structure was confirmed by IR and NMR analysis. Calc. for C17H20BrFO5 : C, 53.41, H, 4.72. Found: C, 53.10, H, 4.66.

Source