A Convenient Synthesis of Unsymmetrical Pinacols by Coupling of Structurally Similar Aromatic Aldehydes Mediated by Low-Valent Titanium
Xin-Fang Duan*, Jian-Xia Feng, Guo-Fu Zi, Zhan-Bin Zhang
*Department of Chemistry, Beijing Normal University, Beijing, 100875, P. R. of China, Email: xinfangduanvip.163.com
X.-F. Duan, J.-X. Feng, G.-F. Zi, Z.-B. Zhang, Synthesis, 2009, 277-282.
A one-pot, selective cross pinacol-type coupling between two structurally similar aromatic aldehydes in the presence of low-valent titanium gave unsymmetrical pinacols in good yields and diastereoselectivities. This synthetic methodology, which is based on the affinity of the substituents to the surface of titanium, significantly extends the scope of the cross pinacol-type couplings.
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