2001 Fiscal Year Final Research Report Summary
1,4-Addition of Diorganozincs to α,β-Unsaturated Ketones Catalyzed by a Copper(I)-SuIfonamide Combined System.
| Project/Area Number |
12440205
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
物質変換
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| Research Institution | Nagoya University |
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Principal Investigator |
KITAMURA Masato Research Center for Materials Sciences, Nagoya University Professor, 物質科学国際研究センター, 教授 (50169885)
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| Project Period (FY) |
2000 – 2001
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| Keywords | diorganozincs / α,β-unsaturated ketones / Copper(I)-Sulfomamide combined syste / catalytic 1,4-addition / bifunctional catalyst / three-component coupling / kinetics |
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| Research Abstract |
A mixture of CuCN and N-benzylbenzenesulfnamide catalyzes the 1,4-addition of dialkylzincs or diarylzincs(Cu : Zn = 1 : 200 to l : 10000)to α,β-unsaturated ketones to give, after aqueous workup, the corresponding β-substituted ketones in nearly quantitative yields. A range to cyclic enones having-s-cis or s-trans geometries as well as conformationally flexible acyclic enones are usable as substrates. The ethyl group migrates more readily than the methy and phenyl groups. CuOTf, CuO-t-C_4,H_9, and mesitylcopper can be used in place of CuCN. The in situ-formed alkylzinc enolate, prior to aqueous workup, further undergoes an aldol reaction with aldehydes or Pd(0)-assisted coupling with allyl acetate, resulting in regio-controlled, vicinal carbacondensation products. A catalytic cycle is proposed on the basis of a kinetic study and a structural analysis of the zinc enolate product by NMR and molecular weight measurements.
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