Abstract
An efficient catalytic method has been developed for the enantioselective
synthesis of functionalized diarylmethanols starting from aryl bromides
and aldehydes. In the presence of (R )-3-(3,5-diphenylphenyl)BINOL
(2 mol%) and titanium tetraisopropoxide, functionalized
aryl Grignard reagents (FGArMgCl; FG = 3-F3 C,
4-F3 C, 3-Br, 3-CN, 4-CN), prepared in situ by treatment
of the bromides with i -PrMgCl˙LiCl,
undergo addition to aldehydes to give the corresponding functionalized
diarylmethanols in high enantioselectivities.
Key words
aldehydes - arylation - asymmetric catalysis - magnesium - titanium
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