A mixture of 2-(2-chloro-1-chloromethyl-ethoxy)-6-(naphthalene-1-sulfonylmethyl)-phenylamine (4) (2 g, 4.77 mmoles) in THF and 4M HCl (15 ml) was stirred, under nitrogen, at 3° C., treated dropwise with a solution of sodium nitrite (0.34 g, 5 mmoles) in H2O (2 ml). The reaction mixture was poured into a cold solution of saturated sodium bicarbonate and extracted with EtOAc. The extracts were combined, dried over Na2SO4 and concentrated under vacuum to afford the title compound as an off white solid (1.76 g, 4.05 mmoles), identified by HNMR analysis.
