New chiral ferrocenyloxazolines: The first planar chiral triferrocenylmethane derivative and its use in asymmetric catalysis

New planar chiral enantiopure ferrocenyloxazolines have been prepared including ferrocenyldiphenylmethanol, diferrocenylphenylmethanol and triferrocenylmethanol derivatives (S,pR)-10 – (S,pR)-12, the latter being the first chiral triferrocenylmethanol derivative. The ferrocenyldiphenylmethanol derivative (S,pR)-10 has been crystallographically characterized. Asymmetric ethylation of some arylaldehydes using diethylzinc in the presence of the planar chiral triferrocenylmethanol derivative (S,pR)-12 afforded good yields and ees, which were higher than those obtained with related ferrocenyloxazolines.

Graphical abstractNew planar chiral enantiopure ferrocenyloxazolines have been prepared including ferrocenyldiphenylmethanol, diferrocenylphenylmethanol and triferrocenylmethanol derivatives, the latter being the first chiral triferrocenylmethanol derivative. The ferrocenyldiphenylmethanol derivative has been crystallographically characterized. Asymmetric ethylation of some arylaldehydes using diethylzinc in the presence of the planar chiral triferrocenylmethanol derivative afforded good yields and ees.Figure optionsDownload full-size imageDownload as PowerPoint slide