• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1851-1854
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• 2014

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1359-1365
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• 2005

A series of new chiral [iminophosphoranyl]ferrocenes, {${\eta}^5-C_5H_4-(PPh_2=N-2,6-R_2-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-PPh^2-2-CH(Me)NMe_2$} (1: R = Me, $^iPr$), {${\eta}^5{-C_5H_4-(PPh_2=N-2,6-R_2}^1-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-(PPh_2=N-2,6-R_2-C_6H_3)-2-CH(Me)R_2$} (2: $R^1\;=\;Me,\;^iPr;\;R^2\;=\;NMe_2$, OMe), and $({\eta}^5-C_5H_5)Fe${${\eta}^5-C_5H_4-1-PR_2-2-CH(Me)N=PPh_3$} (3:R = Ph, $C_6H_{11}$) have been prepared from the reaction of [1,1'-diphenylphosphino-2-(N,N-dimethylamino) ethyl]ferrocene with arylazides (1 & 2) and the reaction of phosphine dichlorides ($R_3PCl_{2}$) with [1,1'-diphenylphosphino-2-aminoethyl]ferrocene (3), respectively. They form palladium complexes of the type $[Pd(C_3H_5)(L)]BF_4$ (4-6: L = 1-3), where the ligand (L) adopts an ${\eta}^2-N,N\;(2)\;or\;{\eta}^2$-P,N (3) as expected. In the case of 1, a potential terdentate, an ${\eta}^2$-P,N mode is realized with the exclusion of the –=NAr group from the coordination sphere. Complexes 4-6 were employed as catalysts for allylic alkylation of 1,3-diphenylallyl acetate leading to an almost stoichiometric product yield with modest enantiomeric excess (up to 74% ee). Rh(I)-complexes incorporating 1-3 were also prepared in situ for allylic alkylation of cinnamyl acetate as a probe for both regio- and enantioselectivities of the reaction. The reaction exhibited high regiocontrol in favor of a linear achiral isomer regardless of the ligand employed.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1617-1621
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• 2012

The titanate nanotube (TNT) was hydrothermally synthesized in 10 M NaOH aqueous solution at $150^{\circ}C$ for 72 h. Titanate nanotube with high surface area (292 $m^2$/g) is a good candidate as a support for catalytic reaction or organic synthesis. Palladium nanoparticles with an average size of $ca$. 3 nm were well dispersed onto the surface of TNT nanotubes. Palladium loaded catalyst with high surface area shows a highly efficient ${\alpha}$ alkylation of ketones with primary alcohols.

• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.958-962
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• 2001

The chiral amine auxiliary mediated stereoselective alkylation reactions of glycinamides 1-6 and 15-17 using phase transfer catalyst (PTC) for liquid-solid extraction are described. The secondary N-(diphenylmethylene) glycinamides 1, 2 and 3 give better selectivities and yields than tertiary N-(diphenylmethylene) glycinamides 4, 5 and 6. Alkylation of the glycinamide 1 and 2 using 18-Crown-6 as a PTC in toluene at $-40^{\circ}C$ gives best selectivities and yields. Alkylations of N-(4-chlorophenylmethylene)glycinamides 15, 16 and 17 under same PTC conditions give $\alpha$, $\alpha-disubstituted$ amino acid derivatives 18, 19 and 20 with low diastereoselectivities.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4133-4136
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• 2011

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.915-916
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• 2007

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.347-350
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• 2015

In this study, ionic liquids have been employed as a green catalyst in the alkylation of isobutane with 2-butene. One of acid ionic liquids, 1-octyl-3-methylimidazolium-bromide-aluminum chloride, was used in the reaction. Effects of the liquid hourly space velocity (LHSV), reaction temperature and composition of ionic liquids on the reaction performance were investigated in order to optimize reaction conditions. Under identical reaction conditions, the optimum reaction temperature was $80^{\circ}C$ and the ionic liquid with the anion composition of 0.56 showed an excellent reaction activity. Moreover, a correlation model was developed with a statistical approach to predict the product yields.

• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.980-981
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• 1996

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.612-614
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• 1994

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.129-141
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• 2005

(-)-Fumagillol (1), a hydrolysis product of fumagillin, has been synthesized by several group from commercially available 1,2:5,6-di-O-isopropylidene-${\alpha}$-D-allofuranose in a highly stereoselective manner. Chiral centers on C5 and C6 came from D-allofuranose and the asymmetric center on C4 was accomplished by 1,3-chirality transfer using the Claisen rearrangement on a chiral allyl alcohol. Chirality, which is necessary on an epoxide consisting of the spiro-ring system, was diastereoselectively constructed by the well-known reaction, intramolecular ester enolate alkylation (IEEA), which showed that this reaction can be applied to the alpha-alkoxy ester system. The epoxide on the side chain was regioselectively introduced by the difference between the number of substituents on the vinyl groups. This accomplishment proved that IEEA can be a useful tool for the synthesis of complex molecules.