Monophenylation of diols

Barton et al. (92) discovered that the monophenylation of diols using triarylbis-muth reagents may be catalyzed by Cu(II) salts. Brunner has examined various ligands in this reaction and found that modest enantioselectivities are observed in the... 

DAVID-THIEFFRY Monophenylation of Diols Selective phenylation of one hydroxyl group of glycols by triphenylbismuth diacetate. 

Monophenylation of dials. Isolated hydroxyl groups are inert to 1, but diols are converted into monophenyl ethers on reaction with 1 in refluxing CH Cl,. Yields are high in reactions with vtc-diols, but fall to 40-50% when the hydroxyl groups are separated by three or four methylene groups. In the reactions of /-butylcyclohexanediols with 1, the axial epimer reacts much more rapidly than the equatorial one. Preferential phenylation of axial hydroxy groups of pyranosides is also observed. 

Monophenylation of cis-Dioh. Monophenylation of cw-diols derived from cyclopentane and cyclohexane using triphenyl-bismuthdiacetate, (S)-(-)-4-(2-methylpropyl)-2-(2-pyridyl)-2-oxazoline as the ligand (L ), and Cu(OAc)2 as a co-catalyst affords the products in moderate yields (38-54%) and enantioselectivities (13-44% ee) (eq 2). ... 

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