Please use this identifier to cite or link to this item:
|Title:||Chiral metal template induced asymmetric synthesis of a mixed phosphine-phosphine oxide ligand|
|Authors:||Yeo, W.-C. |
|Citation:||Yeo, W.-C., Tang, L., Yan, B., Tee, S.-Y., Koh, L.L., Tan, G.-K., Leung, P.-H. (2005-11-07). Chiral metal template induced asymmetric synthesis of a mixed phosphine-phosphine oxide ligand. Organometallics 24 (23) : 5581-5585. ScholarBank@NUS Repository. https://doi.org/10.1021/om0505662|
|Abstract:||The asymmetric hydrophosphination reaction of 1,1-bis(diphenylphosphino) ethene and diphenylphosphine promoted by a chiral organopalladium(II) complex derived from (S)-N,N-dimethyl-1-(1-naphthyl)ethylamine proceeded stereoselectively to generate an equilibrium mixture of four diastereomeric triphosphine palladium(II) template products in a ratio of 17:5:3:2. Alternatively, the direct coordination of 1,1,2-tris(diphenylphosphino)ethane to the chiral organopalladium template generated the same equilibrium mixture of diastereomeric products with the same stereoselectivity. Subsequent asymmetric oxidation of the diastereomeric template products with hydrogen peroxide proceeded stereoselectively to generate four diastereomeric monooxidation products in the ratio of 14:3:3:1. The effects of solvent, temperature, and alternative oxidizing agents were also studied. The naphthylamine auxiliary was removed chemoselectively from the template products by treatment with concentrated hydrochloric acid to form an enantiomerically enriched mixture of the corresponding dichloro complexes, which upon subsequent repeated recrystallization gave the predominant enantiomeric complex in its optically pure form. Further ligand displacement of the enantiomerically pure dichloro complex with aqueous cyanide liberated the free mixed phosphine-phosphine oxide ligand in quantitative yield. © 2005 American Chemical Society.|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Dec 7, 2018
WEB OF SCIENCETM
checked on Nov 21, 2018
checked on Dec 8, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.