Reaktion #74255

Reaktionsgleichung

HCl

1,8-diazabicyclo[5.4.0]undec-7-ene

methyl 2-bromocyclooctene-3-glycolate

methyl 2-bromocyclooct-1-en-3-glycolate

DBU

→

cyclooct-1-yn-3-glycolic acid

Ausbeute 55.0%

Lösungsmittel

DMSO

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe combined mixture is stirred overnight at 60° C
2. 2
   Extraktionextracted with AcOEt
3. 3
   FiltrationThe organic phase is filtered through a separating
4. 4
   Filtrationfilter
5. 5
   Einengenis concentrated under vacuum
6. 6
   SonstigeThe cyclooct-1-yn-3-glycolic acid 18 is purified on a preparative plate (CH2Cl2/MeOH 9/1)
7. 7
   Sonstigeis obtained with a yield of 55% (w=50 mg)

Vorschrift

150 μl of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 1 mmol) are added to a solution of methyl 2-bromocyclooctene-3-glycolate 17 (0.5 mmol) in anhydrous DMSO at 60° C. After stirring for 15 min, an additional 600 μl of DBU (4 mmol) are added and then the combined mixture is stirred overnight at 60° C. The mixture is acidified with 1M HCl and extracted with AcOEt. The organic phase is filtered through a separating filter and is concentrated under vacuum. The cyclooct-1-yn-3-glycolic acid 18 is purified on a preparative plate (CH2Cl2/MeOH 9/1) and is obtained with a yield of 55% (w=50 mg).

Quelle