ISSN:
0009-2940
Keywords:
Ether phosphanes
;
Hydroxyalkylphosphanes
;
Rhodium
;
Asymmetric hydrogenation
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Optically pure 1,4-bis(diphenylphosphanyl)-2-hydroxy-butane (2) and its methyl ether 1 can be conveniently prepared by starting from chiral pool substances such as malic or L-ascorbic acid. Different pathways to these compounds were elucidated. In one case an interesting migration of an acetalic OH-protective group was observed. The reaction of the bisphosphanes with Rh1 or PdII gave uniform metal complexes. On the basis of X-ray structural analysis, NMR and IR data it was concluded that in the investigated precatalysts of the type [Rh(COD)(bisphosphane)]BF4 a coordination of the alkoxy or hydroxy oxygen to the metal does not take place. Nevertheless, significant differences in enantioselectivity and activity could be observed when several prochiral substrates were hydrogenated.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19951280805
Permalink
