Water → 4-Amino-1-naphthoic acid

4-Amino-1-naphthalenecarbonitrile (1.5 g, 8.91 mmol) was suspended in a 50% KOH solution (18 mL). The heterogeneous solution was heated at reflux for 2-3 days. Once the solution became homogeneous and TLC showed no more starting material, the deep red solution was cooled and poured over 200 mL of water. The resulting solution was then filtered and the desired product was precipitated with concentrated HCl. The resulting red crystals were filtered and the filtrate was refiltered to give pink crystals. The first fraction of crystals was treated with activated carbon to remove some of the red color. A total of 1.51 g of the desired product was obtained: m.p. 169-171° C.;

1. temperatureThe heterogeneous solution was heated
2. temperatureat reflux for 2-3 days
3. temperaturethe deep red solution was cooled
4. filtrationThe resulting solution was then filtered
5. customthe desired product was precipitated with concentrated HCl
6. filtrationThe resulting red crystals were filtered
7. customto give pink crystals
8. additionThe first fraction of crystals was treated with activated carbon
9. customto remove some of the red color

ORD-Eintrag

ord-4b6949065115427c94ed2c7f7d433fb2

Quelldatensatz

uspto-grants-2001_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06310095B1