State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
J Am Chem Soc. 2020 Nov 11;142(45):19354-19359. doi: 10.1021/jacs.0c09638. Epub 2020 Nov 3.
Spirocyclic hexadienones with multiple stereogenic centers are frequently found in natural products but remain challenging targets to synthesize. Herein, we report the enantioselective desymmetrization of bisphenol derivatives via Ir-catalyzed allylic dearomatization reactions, affording spirocyclic hexadienone derivatives with up to three contiguous stereogenic centers in good yields (up to 90%) and excellent enantioselectivity (up to 99% ee). The high efficiency of this reaction is exemplified by the short reaction time (30 min), low catalyst loading (down to 0.2 mol %), and ability to perform the reaction on a gram-scale. The total syntheses of (+)-tatanan B and (+)-tatanan C were also realized using this Ir-catalyzed allylic dearomatization reaction as a key step.
具有多个手性中心的螺环六烯酮在天然产物中经常被发现，但它们仍然是具有挑战性的合成目标。在此，我们报告了通过 Ir 催化的烯丙基去芳构化反应对双酚衍生物进行对映选择性去对称化，以高收率（高达 90%）和优异的对映选择性（高达 99%ee）获得具有多达三个连续手性中心的螺环六烯酮衍生物。该反应的高效率体现在反应时间短（30 分钟）、催化剂负载量低（低至 0.2mol%）和能够在克级规模上进行反应。（+）-tatanan B 和（+）-tatanan C 的全合成也使用该 Ir 催化的烯丙基去芳构化反应作为关键步骤来实现。
