Abstract
Salen-type Schiff base ligands incorporating two different benzylidene moieties and a diamine backbone were synthesized in high yield (80-90%) under mild conditions via a stepwise approach. In the first step, anhydrous hydrochloric acid was used to selectively protect one amino group of the vicinal diamine backbone. The resulting ammonium salt was added to a substituted benzaldehyde providing access to a mono-imine product. This compound reacted with an equivalent of a different benzaldehyde in the presence of triethylamine to afford an unsymmetrical salen-type ligand. This synthetic method allows facile access to a plethora of salen-type Schiff base ligands with easily tunable steric and electronic properties.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1221-1225 |
| Number of pages | 5 |
| Journal | Tetrahedron Letters |
| Volume | 42 |
| Issue number | 7 |
| DOIs | |
| State | Published - Feb 12 2001 |
Funding
Support from the Dupont company and the Beckman, Dreyfus, and Packard Foundations are gratefully acknowledged. E.J.C. acknowledges the GEM and IMGIP fellowship programs for financial support. We thank the NIH for their support in the purchase of the Micromass Quatro II triple quadrupole electrospray mass spectrometer (grant S10 RR11320). We thank Mark Staples and Dr. Hongying Zhou for their helpful discussion and Brian Kane for his technical help.
ASJC Scopus subject areas
- Biochemistry
- Drug Discovery
- Organic Chemistry