Reaktion #6396

Reaktionsgleichung

17-ethyl-1-hydroxy-12-[2'-(3",4"-dihydroxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone

isopropyl trichloroacetimidate

Trifluoromethanesulfonic acid

→

title compound

17-Ethyl-1-hydroxy-12-[2'-(4"-hydroxy-3"-isopropoxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONto mix for 5 minutes
2. 2
   SonstigeAfter 24 hours the reaction was quenched by the addition of saturated sodium bicarbonate
3. 3
   Extraktionextracted with ethyl acetate (3×8 ml)
4. 4
   WaschenThe combined organics were washed with brine
5. 5
   Trocknendried over magnesium sulfate
6. 6
   SonstigePurification of the
7. 7
   Einengenconcentrate by preparative TLC on silica gel (ethyl acetate:hexane (1:1)+1% methanol)

Vorschrift

To a solution of 17-ethyl-1-hydroxy-12-[2'-(3",4"-dihydroxycyclohexyl)-1'-methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4-azatricyclo[22.3.1.04,9 ]octacos-18-ene-2,3,10,16-tetraone (69 mg in 3 ml 33% methylene chloride in cyclohexane), isopropyl trichloroacetimidate (22 μl neat) was added and the reagents allowed to mix for 5 minutes. Trifluoromethanesulfonic acid (2μl neat) was added slowly via syringe and the mixture stirred at room temperature. After 24 hours the reaction was quenched by the addition of saturated sodium bicarbonate and extracted with ethyl acetate (3×8 ml). The combined organics were washed with brine and dried over magnesium sulfate. Purification of the concentrate by preparative TLC on silica gel (ethyl acetate:hexane (1:1)+1% methanol) gave the title compound (12 mg).

Quelle