Asymmetric Total Synthesis of the Highly Strained 4β-Acetoxyprobotryane-9β,15α-diol
Wen Zhang1,2, Zi-Xiong Zhou1, Xu-Jiang Zhu1
1Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalytic Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.
Abstract:
The first and asymmetric total synthesis of 4β-acetoxyprobotryane-9β,15α-diol, containing a rare and highly strained trans-fused bicyclo[3.3.0]octane ring system, has been achieved. The synthetically challenging [6-5-5] tricyclic ring system in the final product was efficiently and diastereoselectively synthesized via an asymmetric rhodium-catalyzed [4 + 2] cycloaddition reaction, followed by a unique benzilic acid type rearrangement under very mild conditions. The seven contiguous stereocenters were installed efficiently and diastereoselectively.
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