تفاعل #960940

معادلة التفاعل

di-tert-butyl (6′-bromotrispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-yl)imidodicarbonate

5-methylpyridine-3-boronic acid

Na2CO3

charcoal

→

6′-(5-methylpyridin-3-yl)trispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-amine

المردود 75.3%

المذيبات

dioxane H2O

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGthe mixture was stirred for 10 minutes at 50° C
2. 2
   ترشيحThe mixture was filtered through celite pad (eluted with EtOAc)
3. 3
   غسيلthe filtrate was washed with H2O and brine
4. 4
   تجفيفThe organic layer was dried over MgSO4
5. 5
   ترشيحfiltered
6. 6
   تركيزthe filtrate was concentrated under reduced pressure
7. 7
   workup.ADDITIONTo the residue were added toluene (3.0 mL) and silica gel (neutral; 900 mg)
8. 8
   workup.STIRRINGthe mixture was stirred for 3 hours at 120° C
9. 9
   أخرىAfter concentration of the reaction mixture at reduced pressure, the residue was purified with column chromatography on silica gel (CHCl3-EtOH

الإجراء التجريبي

A mixture of di-tert-butyl (6′-bromotrispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-yl)imidodicarbonate (300 mg, 0.531 mmol), 5-methylpyridine-3-boronic acid (145 mg, 1.06 mmol), bis(triphenylphosphine)palladium(II) dichloride (37 mg, 0.053 mmol) and Na2CO3 (169 mg, 1.59 mmol) in dioxane-H2O (4:1, 6.0 mL) was stirred for 1 hour at 100° C. To the mixture was added charcoal and the mixture was stirred for 10 minutes at 50° C. The mixture was filtered through celite pad (eluted with EtOAc) and the filtrate was washed with H2O and brine. The organic layer was dried over MgSO4 and filtered, and the filtrate was concentrated under reduced pressure. To the residue were added toluene (3.0 mL) and silica gel (neutral; 900 mg), and the mixture was stirred for 3 hours at 120° C. After concentration of the reaction mixture at reduced pressure, the residue was purified with column chromatography on silica gel (CHCl3-EtOH, a linear gradient of EtOH from 0 to 20%) to afford 6′-(5-methylpyridin-3-yl)trispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-amine (151 mg).

المصدر