The new C-2-symmetrical diphosphines 1-4 of potential interest for asy
mmetric catalysis were prepared in protected form by a convergent synt
hesis based on the use of readily available (S,S)-1,2-cyclohexanedicar
boxylic acid 8 and the phosphorus reagent(Et2N)(2)PLi . BH3. (C) 1997
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