• Bulletin of the Korean Chemical Society
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• v.17 no.8
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• pp.725-729
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• 1996

Reaction of carbonyl compounds with B-alkoxydiisopinocampheylborane (Ipc2BOR, R=H, Et, i-Pr, t-Bu) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents were extremely mild and reduced only aldehydes effectively under mild conditions. The reagents also reduced α,β-unsaturated aldehydes to the corresponding allylic alcohols without any detectable 1,4-reduction. Furthermore, aldehydes can be reduced in the presence of epoxides and acid chlorides. Consequently, the selective reduction of aldehyde groups in the presence of keto and all other functional groups has been realized with these reagents.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.162-165
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• 1987

The reduction rate of borohydride exchange resin (BER) was greatly enhanced in the presence of lithium salts. Thus 2-heptanone was reduced completely with BER-LiCl in 1 h at room temperature. However, no reduction was observed with BER alone under the same conditions. With this system, organic compounds containing various fuctional groups were examined in ethanol at room temperature. This study revealed that BER-LiCl system exhibits an excellent chemoselectivity for carbonyl group in the presence of other functional groups. Keto esters and epoxy ketones were reduced with BER-LiCl to give the corresponding hydroxy esters and epoxy alcohols with excellent yields. Selective reductions of carbonyl groups were also possible in the presence of other organic compounds containing functional groups such as 1-idooctane, 1-bromooctane, caproamide, hexanenitrile, nitrobenzene, n-butyl disulfide, dimethyl sulfoxide and 1-dodecene.

• Journal of Integrative Natural Science
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• v.1 no.3
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• pp.192-194
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• 2008

A series of non-free hydride reducing systems containing boron or aluminum atom, which possess no metal-hydride bond but an available hydrogen at a branched ${\beta}$-position, has been applied to the selective reduction (chemo--, regio-, and stereoselective reduction) of organic compounds. The systems, comprised of diisopinocampheylborane and diisobutylalane derivatives, exhibited almost perfect selectivities in the reduction of aldehydes and ketones. The characteristics features of this systems leading to a perfect transformation have been depicted in this report, especially in the 1) Reduction of ${\alpha}$,${\beta}$-Unsaturated Carbonyl Compounds to Allylic Alcohols via 1,2-Reduction, 2) Chemoselective Reduction between Structurally Different Carbonyl Compounds, and 3) Stereoselective Reduction of Cyclic Ketones.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1658-1660
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• 2009

• Bulletin of the Korean Chemical Society
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• v.17 no.10
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• pp.900-905
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• 1996

Details are described of reaction of carbonyl compounds with diisobutyldialkylaminoalane (DIBAL-NR2; R=Et, i-Bu, Ph) in order to establish their reduction characteristics. The reagents were extremely mild and reduced only aldehydes and ketones effectively in ethyl ether at 25 ℃. The stereoselectivity in the reduction of representative cyclic ketones appeared not so high but quite different from that obtained by DIBAL-H itself. The reagents reduced α,β-unsaturated aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction products. DIBAL-NR2 also achieved the selective reduction of aldehydes or ketones in the presence of keto or other readily reducible functional group, however the chemoselectivity was less satisfactory than that achieved by diisobutylethoxyalane (DI-BAL-OEt).

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1051-1052
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• 2002

• Journal of the Korean Society of Tobacco Science
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• v.26 no.2 s.52
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• pp.159-167
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• 2004

This work has been conducted to select appropriate filter materials for removing carbonyl compounds in mainstream tobacco smoke. To investigate of the usability of this filter materials, two types of bead ion exchangers were synthesized and their adsorption characteristics for carbonyl compounds were investigated. Sulfonic acid group-containing cation exchanger and ammonium group-containing anion exchanger were synthesized by the suspension polymerization of glycidylmethacrylate(GMA) and divinylbenzene(DVB) followed by the subsequent functionalization, respectively. The removal efficiency of carbonyl compounds by these two ion exchangers increased in the presence of moisture. However, the amount of carbonyl compounds adsorbed on the anion exchanger was larger than that on the cation exchanger under two levels of water contents tested. This phenomenon seems to arise from the electron delocalization in carbonyl group of the anion exchangers. There was not any significant relationship between the amount of carbonyl compounds adsorbed on ion exchangers and the length of adsorption column. From the large ion exchange capacity and rapid ion exchange reaction rate of the anion exchanger, it is suggested that the anion exchanger may be a good filter material for removing carbonyl compounds in the mainstream tobacco smoke.

• Bulletin of the Korean Chemical Society
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• v.17 no.1
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• pp.50-55
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• 1996

Reaction of carbonyl compounds with diisopinocampheylhaloboranes (Ipc2BX,X=Cl, Br, I) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents reduced aldehydes and ketones to the corresponding alcohols. The reactivities are in the order of Ipc2BCl Ipc2BBr>Ipc2BI.The reagents also reduced ${\alpha}{\beta}-unsaturated$, aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Especially, the chloro derivative nicely achieved the selective reduction of aldehyde or ketone groups in the presence of many other functional groups. The most remarkable result of this investigation is that aldehydes and ketones can be selectively reduced in the presence of acid chlorides.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.236-242
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• 1998

Reaction of carbonyl compounds with Al-alkoxydiisobutylalane (DIBAOR, R=H, Et, i-Pr, t-Bu) has been investigated in detail so as to establish their usefulness as selective reducing agents in organic synthesis. The reagents appear to be extremely mild and can reduce only aldehydes and ketones effectively under mild conditions. All the other common organic functional groups are not affected by these reagents. The reagents can also reduce α,β-unsaturated aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Furthermore, the reagents show a highly chemoselective discrimination between aldehyde and ketone, between aldehydes, and between ketones. Even more remarkable is the stereoselective reduction of cyclic ketones to the thermodynamically more stable alcohol epimers.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.375-381
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• 2006

Aldehyde reductase was purified to electrophoretic homogeneity from Saccharomyces cerevisiae, and then enzymatic reduction of substituted carbonyl compounds was carried out by using the purified aldehyde reductase as a biocatalyst. Under preparative scale reaction renditions, the enzymatic reduction proceeded in high chemical yield with excellent chemoselectivity. The enzymatic reduction product was identified by TLC, GC, Mass, NMR and FT-IR. Benzoic acid, an inhibitor of aldehyde reductase, also potently inhibited the reduction of substituded carbonyl compounds. This enzyme exhibited a broad substrate specificity , and can utilize both NADH and NADPH as cofactors. The enzyme was strongly inhibited by benzoic acid and quercetin. The apparent Km for 4-cyanobenzaldehyde and 3-nitrobenzamide were 4.894 mM and 0.305 mM, respectively.