Hydrochloric Acid → N-(5-Bromonaphthalene-1-carbothioyl)-N-methylglycine

Reaction equation

[OH-].[Na+].C[O:4][C:5](=[O:22])[CH2:6][N:7]([C:9]([C:11]1[C:20]2[C:15](=[C:16]([Br:21])[CH:17]=[CH:18][CH:19]=2)[CH:14]=[CH:13][CH:12]=1)=[S:10])[CH3:8].Cl>CO>[Br:21][C:16]1[CH:17]=[CH:18][CH:19]=[C:20]2[C:15]=1[CH:14]=[CH:13][CH:12]=[C:11]2[C:9](=[S:10])[N:7]([CH3:8])[CH2:6][C:5]([OH:22])=[O:4]

Participants

Procedure

A 1 N aqueous NaOH solution (25 ml) was added to a suspension of N-[(5-bromo-1-naphthalenyl)thioxomethyl]-N-methylglycine methyl ester (7.3 g, 20.7 mmoles; described in Example 3) in methanol (75 ml). The mixture was stirred at 20° to 22° C. for 21/2 hr, neutralized to pH 7 with aqueous HCl and concentrated under reduced pressure to remove methanol. The residual solution was rendered acidic (pH=2) with the addition of aqueous HCl solution and extracted with ethyl acetate. The extract was dried (MgSO4) and evaporated to dryness. The residue was crystallized from ethyl acetate-hexane to give 5.3 g of the title compound; mp 181° C.; NMR (DMSO-d6) δ2.95 (s, 3H), 4.65 & 5.2 (2d, J=16.8, 2H), 7.85 (m, 6H), UVλmax (EtOH) 285 nm (ε12,300), 280 (12,400), 221 (42,600); IR (Nujol™) 2900, 1720 cm-1 ; Anal Calcd: C, 49.72% H, 3.58% N, 4.14%; Found: C, 49.63% H, 3.63% N, 4.18%.