O-Phenylenediamine → HCID 86689298, compound

Participants

Reaction Steps

A 250 mL flask fitted with a stir-bar and condenser was charged with 1,2-phenylenediamine (2.46 g, 22.7 mmol), acid 72 (5.10 g, 22.7 mmol), and 4M HCl (50 mL). The resultant suspension was heated in a 125° C. bath for 72 hr. The mixture was cooled, and concentrated in vacuo to a green solid. The solid was triturated with acetone (50 mL), filtered, and rinsed with acetone (2×20 mL). The solid was then triturated with H2O (50 mL) and filtered. The material was next taken up in MeOH:H2O 1:1 (75 mL), and the pH was adjusted to 11 with 2M NaOH (10 mL). The mixture was then extracted with EtOAc (100 mL). The organic phase was washed with saturated aqueous NH4Cl (50 mL) and brine (50 mL), filtered through phase separation paper, and concentrated in vacuo to a light pink glass. The material crystallized to give 3.95 g of 73 as a white solid (59%). 1H NMR (60 MHz, CDCl3): δ 7.8-7.6 (m, 2H), 7.5-7.0 (m, 3H), 6.6-6.4 (m, 3H), 5.4 (s, 2H), 3.5 (d, 2H), 1.9 (nonet, 1H), 0.9 (d, 6H) ppm. HPLC analysis (15:10:75 H2O:A1:MeOH) showed a purity of 99% with a retention time of 8.5 min.

Provenance & Evidence