Scalable syntheses of the vaulted biaryl ligands VAPOL and VANOL via the cycloaddition/electrocyclization cascade

Z Ding, WEG Osminski, H Ren…

Index: Ding, Zhensheng; Osminski, Wynter E. G.; Ren, Hong; Wulff, William D. Org. Process Res. Dev., 2011 , vol. 15, # 5 p. 1089 - 1107

Full Text: HTML

Citation Number: 18

Abstract

Synthetic approaches to the VANOL and VAPOL ligands are developed which are straightforward, inexpensive, efficient, and amenable to large-scale preparation of the ligands since minimum chromatographic purification is required. The key step in each synthesis is a cycloaddition/electrocyclic ring-opening/electrocyclic ring closure/ tautomerization cascade that provides a direct one-step route to the monomers from which ...