• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.414-418
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• 1987

Electrochemical reduction of dibenzoylmethane was studied on mercury electrode by means of cyclic voltammetry, polarography and potentiostatic measurements in ethanol-water system. In acidic solutions monomeric pinacol was produced by irreversible two-electron process while monomeric and dimeric pinacol were competitively produced by the same process in neutral solution. However, in basic solution the dimeric pinacol was mostly produced through radical by irreversible one-electron transfer process. Mechanisms of the reduction of dibenzoylmethane are deduced from Tafel slope, pH dependance and reaction order with respect to the concentration of dibenzoylmethane in the solution of various pH.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3973-3978
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• 2011

The reductive pinacol coupling reaction of aldehydes or ketones creating a new C-C bond has been a major tool to produce 1,2-diol compounds. The reaction mechanism is known to be composed of sequential three steps (activation, coupling, and dissociation). In this work, we studied the dissociation step of half-titanocene-based catalytic systems. Cp and $Cp^*$ derivatives of the pinacolato-bridged dinuclear complex were synthesized and evaluated as possible models for intermediates from the coupling step. We monitored $^1H$-NMR spectra of the reaction between the metalla-pinacol intermediates and $D_2O$. New reaction routes of the dissociation step including oxo- and pinacolato-dibridged dinuclear complexes and oxo-bridged multinuclear complexes have been suggested.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1246-1248
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• 2006

• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.757-758
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• 2000

• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.842-845
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• 1998

Four new lactones and one dibenzo crown ether were synthesized by reaction of dihydroxy compound with oxalyl chloride and with ${\alpha}$,${\omega}$-dibromo compound, respectively. 5,6,11,12-Tetracarbonyl-2,2,3,3,8,8,9,9-octaphenyl-1,4,7,10-tetraoxacyclodode- cane(1), 5,6,11,12-tetracarbonyl-2,2,3,3,8,8,9,9-octamethyl-1,4,7,10-tetraoxacyclododecane(2), 7,8,15,16-tetracarbonyl-1,6,9,14-tetraoxacylclohexadecane(3), and 5,6,11,12-tetracarbonyl- 2,3,8,9- tetraphenyl-1,4,7,10-tetraoxacyclododecane(4) were prepared by reaction of oxalyl chloride with benzopinacol, pinacol, 2,2'-dihydroxybiphenyl and hydrobenzoin, respectively, in the presence of pyridine. Dibenzo-13-crown-4 (5) was obtained by reaction of catechol with 1,3-dibromopropane/1,2-dibromoethane.