Diphenylethylenediamine
| Diphenylethylenediamine | |
|---|---|
| File:Dpen.png | |
| 1,2-Diphenyl-1,2-diaminoethane | |
| Other names DPEN | |
| style="background: #F8EABA; text-align: center;" colspan="2" | Identifiers | |
| CAS number | 35132-20-8 |
| style="background: #F8EABA; text-align: center;" colspan="2" | Properties | |
| Molecular formula | C14H16N2 |
| Molar mass | 212.29 g/mol |
| Appearance | White crystals |
| Melting point |
79-83 °C |
| Solubility in water | Slightly |
| style="background: #F8EABA; text-align: center;" colspan="2" | Related compounds | |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) | |
| Infobox references | |
1,2-Diphenyl-1,2-ethylenediamine is an organic compound with the formula H2NCHPhCHPhNH2, where Ph is C6H5, phenyl. This diamine is a precursor to a ligand for certain homogeneous hydrogenation catalysts. It can be prepared from benzil by reductive amination.[1]
Optical resolution
DPEN can be obtained as both the chiral and meso diastereomers, depending on the relative stereochemistry of the two CHPhNH2 subunits. The chiral diastereomer, which is of greater value, can be resolved into the R,R- and S,S- enantiomers using tartaric acid as the resolving agent. In methanol, the R,R enantiomer has an specific rotation of [α]23 +106±1°.
TsDPEN
N-tosylated derivative, TsDPENH, is a ligand precursor for catalysts for asymmetric transfer hydrogenation. For example (cymene)Ru(S,S-TsDPEN) catalyzes the hydrogenation of benzil into R,R-hydrobenzoin:[2]
- PhC(O)C(O)Ph + 2 (CH3)2CHOH → PhCH(OH)CH(OH)Ph + 2 (CH3)2CO
References
- ↑ S. Pikul, E. J. Corey (1998), "(1R,2R)-(+)- and (1S,2S)-(-)- 1,2-Diphenyl-1,2-Ethylenediamine", Org. Synth.; Coll. Vol., 9: 387 Missing or empty
|title=(help) - ↑ Takao Ikariya, Shohei Hashiguchi, Kunihiko Murata, and Ryoji Noyori (2005), "Preparation of Optically Active (R,R)-Hydrobenzoin from Benzoin or Benzil", Org. Synth.: 10
