1993 Fiscal Year Final Research Report Summary
DEVELOPMENT OF THE SELECTIVE ORGANIC SYNTHESIS USING MOLYBDENUM ORGANOMETALLICS
| Project/Area Number |
04453097
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Synthetic chemistry
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| Research Institution | YOKOHAMA NATIONAL UNIVERSITY |
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Principal Investigator |
ITO Takashi YOKOHAMA NATIONAL UNIVERSITY, FACULTY OF ENGINEERING, PROFESSOR, 工学部, 教授 (50016721)
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| Co-Investigator(Kenkyū-buntansha) |
MINATO Makoto YOKOHAMA NATIONAL UNIVERSITY, FACULTY OF ENGINEERING, RESEARCH ASSOCIATE, 工学部, 助手 (40239306)
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| Project Period (FY) |
1992 – 1993
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| Keywords | molybdenum / hydride complexes / organic synthesis / cyclopentadienyl ligand / imines / reduction / organometallics / organic carbonyls |
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| Research Abstract |
1. The reactions of bis(cyclopentadienyl)dihydridomolybdenum Cp_2MoH_2and its derivatives with various organic substrates.
(1) The reactions of Cp_2MoH_2 with allylic alcohols in the pesence of p-toluenesulfonic acid yielded cationic eta^3-allyl complexes and gamma-hydroxypropylmolybdenum derivatives, the selectivity of which depended both on the kind of allylic alcohols and the protonic acids employed. The latter products were converted into the molybdenaoxacyclopentane derivatives on treatment with base.
(2) In the presence of protonic acids, Cp_2MoH_2 reduced aldehydes, ketones, and imines to yield corresponding alcohols and amines. In the reduction of prochiral ketones, enantio-selectivity was observed to some extent, whereas in the reduction of imines the reduction in the absence of protonic acid was observed in methanol and the reaction was found to be highly chemoselective.
(3) The monomethycyclopentadienyl derivative, (MeCp)_2MoH_2 was prepared and its reactions similar to described above were exmined in special reference to the substituent effect.
(4) The binuclear complexes bridged by hydroxyl groups [Cp_2M(mu-OH)_2MCp_2]^<2+> were prepared for M = Mo and W which were characterized structurally and their reactions with Lewis bases were investigated.
2. The reactions of [MoH_4(dppe)_2] (dppe = Ph_2PCH_2CH_2PPh_2) with various organic substrates under certain conditions and the examination of the reactivity of their products.
(1) [MoH_4(dppe)_2] reacted with organic amides under the light irradiation to give new (N-acylamido)hydridomolybdenum(II) complexes which were structurally and spectroscopically characterized. The resulting amido complexes were found to react with methanol to give highly reactive dihydriodomethoxo complex [MoH_2(OMe)_2(dppe)_2].
(2) The reactions of [MoH_4(dppe)_2] with substituted malonic diesters were examined in detail and some novel reactions involving selective C-C cleavage were disclosed.
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