32323-53-8Relevant academic research and scientific papers
Phosphoric Acid-Catalyzed Asymmetric Synthesis of SPINOL Derivatives
Li, Shaoyu,Zhang, Ji-Wei,Li, Xian-Lin,Cheng, Dao-Juan,Tan, Bin
, p. 16561 - 16566 (2016)
Axially chiral 1,1′-spirobiindane-7,7′-diol (SPINOL) is the most fundamental and important privileged structure from which other chiral ligands containing a 1,1′-spirobiindane backbone are synthesized. Driven by the development of enantioselective syntheses of axially chiral SPINOL derivatives, we have successfully developed the first phosphoric acid-catalyzed asymmetric approach. This approach is highly convergent and functional group tolerant, efficiently providing SPINOLs in good yield with excellent enantioselectivity, thus delivering a practical and straightforward access to this privileged structure. It should be emphasized that the catalyst loading could be decreased to only 0.1 mol% for the preparative-scale synthesis. Furthermore, 4,4′-dimethyl-SPINOL-phosphoric acid was synthesized and applied to catalyze the model reaction for synthesis of enantioenriched SPINOL derivatives.
