| Abstract
| - The 1,5-dilithiation of o-TMS blocked (dimethylamino)phenylmethylferrocene 4 unexpectedly occurred even thoughone equimolar amount of t-BuLi was used and the 1,5-dilithiated ferrocene 6 was trapped by iodine followed byremoval of the TMS group to give the 1,5-diiodoferrocene11 in a reasonable yield. The 1,5-diiodoferrocene 11 wasconverted into the diastereomer of Taniaphos 12 by sequential dilithiation and trapping with Ph2PCl. The rhodium andcopper complex of 12 catalyzed well the asymmetric allylicalkylation with a Grignard reagent and hydrogenation withthe α-acetamidocinnamic acid ester, respectively, with highenantioselectivities. The methoxy 1,5-diphosphane 14, ofwhich the enantiomer is known as a good ligand for therhodium-catalyzed asymmetric hydrogenation, was obtainedby the inversive substitution of the dimethylamino group of11 by NaOMe and subsequent dilithiation and trapping withPh2PCl.
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