Ethylenediamine → HCID 18764906, compound

This ligand was prepared according to a modified procedure described by Bernal et al in J. Chem. Soc., Dalton Trans, 22, 3667 (1995). First N,N′-bis(pyridin-2ylmethyl)-ethanediamine (bispicen) was synthesised by the following procedure. Ethylenediamine (26 ml, 0.38 mol) was dissolved in 200 ml dry methanol. To this mixture 74 ml (0.76 mol) pyridincarboxaldehyde was added. The mixture was refluxed for 2 h, after which the mixture was left to cool to RT and in small portions 40 g of NaBH4 was added. The mixture was subsequently stirred for 16 h at RT. The methanol was evaporated and 500 ml of water was added. The aqueous mixture was extracted with three portions of dichloromethane (100 ml) and the dichloromethane solution was dried over sodium sulphate, filtered off and the solvent was removed. The dark oil containing N,N′-bis(pyridin-2ylmethyl)-ethanediamine (73.7 g; 81%) was analysed by NMR and used without further purification. 1H-nmr (CDCl3): δ2.20 (br, NH); 2.78 (s, 4H); 3.85 (s, 4H); 7.00-7.40 (m, 4H); 7.58 (m, 2H); 8.45 (m, 2H).

1. customThis ligand was prepared
2. temperatureThe mixture was refluxed for 2 h
3. waitafter which the mixture was left
4. additionwas added
5. customThe methanol was evaporated
6. addition500 ml of water was added
7. extractionThe aqueous mixture was extracted with three portions of dichloromethane (100 ml)
8. dry with materialthe dichloromethane solution was dried over sodium sulphate
9. filtrationfiltered off
10. customthe solvent was removed
11. additionThe dark oil containing N,N′-bis(pyridin-2ylmethyl)-ethanediamine (73.7 g; 81%)
12. customused without further purification

ORD record

ord-c24ccac06e344cdb8d7cc7bb65f86f5c

Source dataset

uspto-grants-2002_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06340661B1