Reacción #336805

Ecuación de reacción

fluorescein isothiocyanate

Et3N

→

fluorescein

Disolventes

DMF

CH2Cl2

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroAn orange colored precipitate was immediately formed
2. 2
   Otroremained during the entire period of the reaction
3. 3
   OtroAfter completion of the reaction
4. 4
   Filtraciónthe insoluble precipitate was filtered off
5. 5
   Otroand the solvent was removed under reduced pressure
6. 6
   workup.ADDITIONThe residue was diluted with CH2Cl2 (15 mL)
7. 7
   Lavadowashed with 1N HCl (2×15 mL) and H2O (2×15 mL)
8. 8
   SecadoThe organic phase was dried over anhydrous Na2SO4
9. 9
   Otroevaporated under reduced pressure

Procedimiento

The starting amine (5) (0.15 g, 0.12 mmol) and fluorescein isothiocyanate (FLITC) (0.056 g, 0.14 mmol) were dissolved in a mixture of DMF and CH2Cl2 (6 mL, 1:5 ratio) at room temperature. The reaction was cooled to 0° C., and then an excess amount of Et3N (66 μL, 0.48 mmol) was added dropwise. An orange colored precipitate was immediately formed and remained during the entire period of the reaction. After completion of the reaction, the insoluble precipitate was filtered off; and the solvent was removed under reduced pressure. The residue was diluted with CH2Cl2 (15 mL), washed with 1N HCl (2×15 mL) and H2O (2×15 mL). The organic phase was dried over anhydrous Na2SO4 and evaporated under reduced pressure to afford 0.18 g (92%) of fluorescein-labeled guanidine (17) as an orange colored foam-shaped solid. 1H NMR (CD3OD): δ 8.20 (s, 1H, ArH), 7.86 (m, 1H, ArH), 7.22 (m, 2H, ArH), 6.64 (m, 3H, ArH), 6.56 (m, 2H, ArH), 3.86 (m, 2H, CH2NHCS), 3.66 (m, 12H, CH2O), 3.46 (m, 6H, CH2NHCO), 3.38 (m, 6H, CH2NH), 2.58 (m, 2H, CH2CO), 2.42 (m, 6H, CH2CO), 1.48 (s, 27H, t-Bu), 1.46 (s, 27H, t-Bu).

Fuente