2006 Fiscal Year Final Research Report Summary
Development of new efficient rearrangement reactions of compounds bearing consecutive hetero atoms
| Project/Area Number |
15590032
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Chemical pharmacy
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| Research Institution | Kobe Pharmaceutical University |
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Principal Investigator |
MIYATA Okiko Kobe Pharmaceutical University, associate professor, 薬学部, 助教授 (90102110)
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| Co-Investigator(Kenkyū-buntansha) |
NAITO Takeaki Kobe Pharmaceutical University, professor, 薬学部, 教授 (00068339)
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| Project Period (FY) |
2003 – 2006
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| Keywords | oxime ether / indole / benzofuran / dienylimine / hydroximate / amino alcohol / hydra zone / arylamine |
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| Research Abstract |
We have developed the new rearrangement reactions of compounds with the two consecutive hetero atoms for the efficient preparations of highly functionalized compounds and heterocycles.
1. The rearrangement reaction of acylenamines adjacent to a heteroatom
We have established a novel [3,3]-sigmatropic rearrangement of N-trifluoroacetyl enehydrazines for synthesis of indolines and indoles. Under the mild conditions, N-trifluoroacetyl enehydrazine having a cyclopentene ring smoothly underwent [3,3]-sigmatropic rearrangement followed by cyclization to give indolines. On the other hand, both cyclohexenyl N-trifluoroacetyl enehydrazine and acyclic N-trifluoroacetyl enehydrazine gave indoles in good yield. The rearrangement of enehydrazine carrying either an o-methoxy or an o-methyl groups gave the dienylimines. The N-trifluoromethanesulfonyl enehydrazine was converted into the rearranged product at low temperature. Similarly, we have found that [3,3]-sigmatropic rearrangement of O-aryloxime et
… More
hers took place smoothly during the course of trifluoroacetylation of 0-aryloxime ether at lower temperature to give the various benzofurans. Furthermore, short and practical syntheses of natural benzofurans were achieved without protection of the hydroxyl group in good overall yield.
2. The rearrangement reaction of imines adjacent to a heteroatom
We have developed imino 1,2-Wittig rearrangement of the hydroximates for the first time. The feasibility of this rearrangement is dependent upon the structure the substrates. The rearrangement of Z-hydroximates proceeded smoothly to give the 2-hydroxyoxime ether in good yield while the corresponding E-isomer gave a mixture of E-and Z-hydroxyoxime ethers. This method was applied to the asymmetric synthesis of (+)-cytoxazone.
3. The rearrangement reaction of amines adjacent to a heteroatom
We have found domino elimination-rearrangement-addition of alkoxy(arylmethyl)amines using organolithium and organomagnesium reagent. This method is suitable for the preparation of a-branched sec-arylamines. Furthermore, we have succeeded in the synthesis of cyclic compounds carrying an azepine ring widely found in biologically active compounds. Less
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Research Products
(18 results)
