... Please enable JavaScript to use all the features on this page. Tetrahedron. Volume 57, Issue 22, 28 May 2001, Pages 4781–4785. Cover image Cover image. ... 4.4.9. 4-(4-Methylpiperazin- 1-yl)benzaldehyde. Yellow solid, 2.98 g, 73%, mp 57–60°C; [Found: C, 70.4; H, 8.0; N, 13.6. ...