1,2-Dicyclohexyl-l -ethanediol

By reduction of the aromatic rings, the enantiomers of 1,2-dicyclohexyl-l, 2-ethanediol 14 are obtained, which have also found application for the alkylation of carbanions via a-haloboronic acids (Section D.1.1.2.1.). 

By use of l,2-dicyclohexyl-l,2-ethanediol as a chiral auxiliary, the chiral (Z)-pentenylboronate 1 has been prepared. This reagent reacts with benzaldehyde with... 

Though the first chiral director used in this work, pinanediol (2), is still the simplest to prepare and there are uses for which it works best, the highest stereoselectivity, up to 1000 1, has been achieved with 1,2-diols of C2 syiiunetiy (3). We now favor (R/ )- or (S. 5)-l,2-dicyclohexyl-l,2-ethanediol [(/ )- or (S> DICHED] for routine use. This dol was introduced by Hoffmann (5), and is easily made via a Sharpless dihydroxylation of irmr-stilbene (6) followed by hydrogenation of the benzene rings over rhodium (7). 

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