• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.329-332
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• 1987

The reaction of (E)-1-alkenyl-1,3,2-benzodioxaboroles with a variety of allylic phenoxides in the presence of a catalytic amount of Pd$(PPh_3)_4$ is described. The reaction affords a general and simple procedure for the preparation of 1,4-alkadienes from alkynes via hydroboration.

• Bulletin of the Korean Chemical Society
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• 제16권2호
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• pp.86-88
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• 1995

• Bulletin of the Korean Chemical Society
• /
• 제16권9호
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• pp.797-799
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• 1995

• Bulletin of the Korean Chemical Society
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• 제8권6호
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• pp.484-485
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• 1987

• Bulletin of the Korean Chemical Society
• /
• 제16권11호
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• pp.1126-1128
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• 1995

• Bulletin of the Korean Chemical Society
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• 제19권11호
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• pp.1257-1261
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• 1998

• Bulletin of the Korean Chemical Society
• /
• 제9권4호
• /
• pp.257-258
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• 1988

• Bulletin of the Korean Chemical Society
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• 제7권2호
• /
• pp.160-162
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• 1986

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2153-2161
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• 2007

The transition metal-induced in situ generation of carbene complexes from alkynes having a carbonyl or imino group as a nucleophilic functionality has been investigated. These reactive carbenoid species are generated with high atom efficiency through a 6-endo-dig cyclization mode based on the electrocyclization of vinylidene complexes or a 5-exo-dig cyclization mode in π-alkyne complexes, and have been found to serve as versatile intermediates in catalytic carbene transfer reactions. Highlighted and reviewed in this account are the generation and preparation of pyranylidene, furylcarbene, pyrrolylcarbene, and vinylcarbene complexes and their application to [3,3]sigmatropic rearrangement of acylcyclopropylvinylidenes, catalytic cyclopropanation reactions, [2,3]sigmatropic rearrangement or condensation reactions via ylides, ring-opening and substitution reactions with heteroaromatic compounds, and catalytic isomerization of oligoynes.

• Bulletin of the Korean Chemical Society
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• 제16권1호
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• pp.37-42
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• 1995

Reactions of alkenes and alkynes with the recently discovered isopinocampheylhaloborane-methyl sulfide (IpcBHX·SMe2, X=Cl, Br, I) were investigated in detail in order to establish their usefulness as hydroborating agents. The reagents readily hydroborated alkenes at 50 ℃ and alkynes at 25 ℃ with excellent regioselectivity in placing the boron atom exclusively at the less hindered carbon atom. Especially, the selectivity achieved by the iodo derivative reaches essentially 100%. In addition to that, IpcBHX·SMe2 was applied to the reduction of cyclic ketones to examine its stereoselectivity. The halogen substituent in these reagents plays an important role in the stereoselective reduction. The stereoselectivity increased dramatically with increasing steric size of the substituent. Finally, the iodo derivative achieved highly stereoselective reduction, such selectivity being comparable to that previously achieved with trialkylborohydrides.