Chelation-control in nucleophilic addition to Cr(CO)3-complexed aryl aldehydes.

@article{Tipparaju2003ChelationcontrolIN,
  title={Chelation-control in nucleophilic addition to Cr(CO)3-complexed aryl aldehydes.},
  author={Suresh Kumar Tipparaju and Vedavati G. Puranik and Amitabha Sarkar},
  journal={Organic & biomolecular chemistry},
  year={2003},
  volume={1 10},
  pages={1720-5}
}
One or more methoxy groups on the benzylic carbon at the ortho-position of tricarbonylchromium-complexed aryl aldehydes (2, 3 or 4) permit chelation-controlled addition of nucleophiles to the carbonyl function in the presence of Lewis acids. In the absence of a Lewis acid additive, a complementary set of diastereomeric products are obtained.