• Bulletin of the Korean Chemical Society
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• 제15권12호
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• pp.1112-1118
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• 1994

Epoxidation of olefins has been studied using iodosylbenzene (PhIO) as the terminal oxidant and binuclear and mononuclear complexes of $Mn^{2+}$, $Co^{2+}$, and $Cu^{2+}$ as catalysts. Epoxides were the predominant products with trace amounts of allylic oxidation products, and the metal complexes were found to be effective catalysts in the epoxidation reactions. The reactivity of binuclear copper complexes was greater than that of the mononuclear copper complexes, whereas the binuclear and mononuclear complexes of $Mn^{2+}$ and $Co^{2+}$ showed similar reactivities. The nature of the ligands bound to copper did not influence the reactivity of the binuclear copper complexes so long as copper ions were held in close proximity. A metal-iodosylbenzene complex, such as suggested previously for Lewis acidic metal complex-catalyzed epoxidation by iodosylbenzene, is proposed as the active epoxidizing species. Some mechanistic aspects are discussed as well.

• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.410-412
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• 2004

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.2037-2039
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• 2012

• 대한화학회지
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• 제48권2호
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• pp.215-219
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• 2004

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.285-286
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• 2009

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.343-346
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• 2007

• Bulletin of the Korean Chemical Society
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• 제17권5호
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• pp.457-460
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• 1996

The principal elements of the 31P NMR chemical shielding tensors have been determined for three binuclear platinum diphosphite complexes, K4[Pt2(P2O5H2)4·2H2O ("Pt2"), K4[Pt2(P2O5H2)4Cl2]·2H2O ("Pt2Cl2"), and K4[Pt2(P2O5H2)4Br2]·2H2O ("Pt2Br2"), by using a Herzfeld-Berger graphical method for interpreting the 31P MAS spectrum. The orientations of 31P chemical shielding tensor relative to the molecular axis system are partially assigned with combination of the longitudinal relaxation study of HPO32- and the reference to known tensor orientations of related sites; the most chemical shielding component, δ33, is directed along the P-Pt bond axis. A discussion is given in which the experimental principal elements of the 31P chemical shielding tensor are related with the Pt-Pt bond distances in binuclear platinum diphosphite complexes.

• Bulletin of the Korean Chemical Society
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• 제12권2호
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• pp.219-224
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• 1991

New binuclear Ni(Ⅱ) and Cu(Ⅱ) complexes with various alkyl derivatives of 1,2-bis(1,3,6,8,10,13-hexaaza-1-cyclotetradecyl) ethane, in which two fully saturated 14-membered hexaaza macrocyclic subunits are linked together by an ethylene chain, have been synthesized by the one step template condensations of formaldehyde with ethylenediamine and appropriate primary alkyl amines in the presence of the metal ions. Each macrocyclic subunit of the double-ring macrocyclic complexes contains one alkyl pendant arm and has a square planar geometry with a 5-6-5-6 chelate ring sequence. The visible spectra and oxidation properties indicate that the metal-metal interaction of the binuclear complexes are not significant. Synthesis, characterization, and the properties of the complexes are presented.

• Bulletin of the Korean Chemical Society
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• 제29권12호
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• pp.2533-2536
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• 2008

• 분석과학
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• 제13권5호
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• pp.558-564
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• 2000

단핵성 네자리 시프염기인 N,N'-bissalicylidene-1,2-phenylenediamine(BSPD)와 이핵성 네자리 시프 염기 리간드인 N,N',N'',N'''-tetrasalicylidene-3,3',4,4'-tetraaminodiphenyl-methane (TSTM) 및 N, N',N'',N'''-tetrasalicylidene-3,3'-diaminobenzidine (TSDB)을 합성하고, 이들 리간드의 양성자 해리상수를 전위차법으로 구하였다. 합성된 시프염기 리간드들과 Cu(II) 이온을 이용해 착물을 합성하여 순환전압-전류법으로 착물의 특성을 측정한 결과 $Cu(II)_2$-TSTM 착물은 순환전압-전류법에서 두 과정 두 단계의 환원과정으로 두 전자의 확산 지배적인 과정으로 일어남을 알았다. 또한 단핵성 착물 Cu(II)-BSPD와 이핵성 착물 $Cu(II)_2$-TSDB 및 $Cu(II)_2$-TSTM을 ascorbic acid의 산화반응에 이용한 결과, 반응속도는 $Cu(II)_2$ -TSTM>$Cu(II)_2$-TSDB>Cu(II)-BSPD의 순으로 이핵성인 $Cu(II)_2$-TSTM 착물이 가장 큰 값을 가짐을 알았다.