2019 Fiscal Year Annual Research Report
Synthetic Strategies for the Total Synthesis of Pyranonaphthoquinone Type Natural Products
| Project/Area Number |
19K21125
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| Allocation Type | Multi-year Fund |
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| Research Institution | Tokyo Institute of Technology |
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Principal Investigator |
マツリ マーク・マルセロ 東京工業大学, 理学院, 特任助教 (60829315)
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| Project Period (FY) |
2019-04-01 – 2020-03-31
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| Keywords | total synthesis / pyranonapthoquinons / Claisen rearrangement / aromatic polyketides |
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| Outline of Annual Research Achievements |
The efficient and large-scale synthesis of two building blocks has been achieved. For the Synthesis of the aromatic building block, a three-step protocoll has been developed and partly published. The methodology developed includes highly regioselective benzocyclobutenol formation followed by bond-selective ring cleavage and cyclobuten ring opening to access o-methylbenzaldehydes.
An efficient annulation protocol allowed assembly of a naphthalene precursor. The synthesis of a Claisen-precursor was optimized and allowed synthesis of the latter in 12 steps.
The dearomative Claisen rearrangement (CR) was first investigated with a deuterium-labelled model compound. The results strongly suggest a reaction pathway following the classical CR via a 3,3-sigmatropic shift.
Optimization of the reaction conditions for the CR on the real system was developed and comprises a two-step protocol.
The developed synthesis allows for the construction of a synthetic intermediate for ruthmycin bearing the full carbon skeleton with an angular stereogenic center with perfect stereocontrol.
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Research Products
(2 results)
