1996 Fiscal Year Final Research Report Summary
Direct synthetic method for preparation of organotitanium complexes and their synthetic utility
| Project/Area Number |
07455359
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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 |
Synthetic chemistry
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| Research Institution | TOKYO INSTITUTE OF TECHNOLOGY |
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Principal Investigator |
SATO Fumie TOKYO INSTITUTE OF TECHNOLOGY,Biosci. & Biotech., Professor, 生命理工学部, 教授 (50016606)
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| Co-Investigator(Kenkyū-buntansha) |
OKAMOTO Sentaro TOKYO INSTITUTE OF TECHNOLOGY,Biosci.& Biotech., Assistant Professor, 生命理工学部, 助手 (00201989)
URABE Hirokazu TOKYO INSTITUTE OF TECHNOLOGY,Biosci.& Biotech., Assistant Professor, 生命理工学部, 助手 (10176745)
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| Project Period (FY) |
1995 – 1996
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| Keywords | Titanium / Nucleophilicacyl substitution / Ester / Heterocycle / Chiral / Allyltitanium / Aminoacid / Cyclic compound |
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| Research Abstract |
Organic synthesis using titanium (II) complexes has remained unexplored because of the lack of a practical method for synthesis of them. Recently, we have found that the reacition of Ti (O-i-Pr)_4 with 2 equivalent of i-PrMgX provides (eta^2-propene) Ti (O-i-Pr)_2 (1) in essentially quantitative yield and it acts as versatile titanium (II) equivalent. We have now revealed the following synthetically useful reactions using 1.
1) Reaction of cyclic allylic compounds with 1 provides the corresponding cyclic allyltitanium complexes, which in turn react with aldehydes and imines highly stereoselectively.
2) Reaction of 1 with unsaturated esters or carbonates results in intramolecular acyl substitution reaction, thus opening up a new entry cyclic compounds, including N-heterocycles.
3) 1 reacts with alkynes to afford titanium-alkyne complexes which in turn react with optically active aldehydes stereoselectively afforeling allylic alcohols in chiral form.
4) Intramolecular acyl substitution of allenylic carbonates affords a new methodology for synthesizing optically active compounds
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