• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1161-1164
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• 1998

The catalytic transformation of sterically bulky tertiary stannane n-Bu3SnH by the Cp2MCl2/Red-Al (M=Ti, Zr, Hf) and M(CO)6 (M=Cr, Mo, W) catalysts yielded two kinds of catenated products: one is a cross-linked polystannane as minor product, and the other is hexabutyldistannane (n-Bu3Sn)2 as major product. The distannane was produced by simple dehydrocoupling of n-Bu3SnH, whereas the cross-linked polystannane could be obtained via redistribution/dehydrocoupling combination process of n-Bu3SnH. The redistribution/dehydrocoupling combination process may initially produce a low-molecular-weight oligostannane with partial backbone Sn-H bonds which could then undergo an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.74-84
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• 1999

Most of the reactions involving benzotriazoles as a synthetic auxiliary have been explained by ionic mechanisms, whereas benzotriazole-mediated radical reactions have received little attention. The reaction of 1-[(aryl)(phenylseleno)methyl]benzotriazole with $Bu_3$SnH in the presence of AIBN in benzene at reflux gave 2-aminodiphenyl selenide (16-29%), 2-aminobiphenyl (9-15%), diphenyl diselenide (30-93%), 1-(arylmethyl) benzotriazole (9-39%) and tributyltin-phenyl selenide (10-36%), whereas the compounds were treated with excess molar amount of $Bu_3$SnH in the absence of AIBN to afford N-(arylmethyl)anilines (44-66%) along with diphenyl diselenide (53-100%), benzotriazole (27-35%) and 1-(arylmethyl)benzotriazole (16-33%). Similarly, treatment of 6-aryl-6-(benzotriazol-1-yl)-1-hexenyl phenyl selenides with $Bu_3$SnH in the presence of AIBN gave 6-aryl-6-phenylamino-1-hexene (9-31%) and 1-aryl-1-oxo-5-pentene (15-44%). A mechanism for the formation of the products is proposed.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.79-83
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• 2012

Trialkyltin n-$Bu_3SnH$, an endocrine disruptor, was slowly converted by the catalytic action of group 4 $Cp_2MCl_2$/Red-Al (M = Ti, Zr, Hf) to produce two phases of products: one is an insoluble cross-linked solid, polystannane in 7-23% yield as minor product via redistribution/dehydrocoupling combination process, and the other is an oil, hexabutyldistannane in 69-90% yield as major product via simple dehydrocoupling process. Redistribution/dehydrocoupling process first produced a low-molecular-weight oligostannane possessing partial backbone Sn-H bonds which then underwent an extensive cross-linking reaction of backbone Sn-H bonds, leading to an insoluble polystannane. This is the first exciting example of redistribution/dehydrocoupling of a tertiary hydrostannane catalyzed by early transition metallocenes.

• Journal of Integrative Natural Science
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• v.6 no.2
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• pp.71-75
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• 2013

$Bu_3Sn$-endded poly(vinyl)s with biological activity were obtained by the radical polymerization of vinyl monomers using thianthrene cation radical/$^nBu_3H$. Thianthrene cation and stannyl radicals promoted the homopolymerization and copolymerization of styrene and ethyl vinyl ether having number average molecular weights of 2000-3100. Tributyltin hydride functions as a chain transfer agent. Such polymereization by cationic thianthrene and stannyl radicals could provide some clues for the biological reaction in living animals. Plausible polymerization mechanisms were suggested.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1440-1442
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• 2005

• Applied Biological Chemistry
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• v.49 no.4
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• pp.339-342
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• 2006

Canna generalis was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. from the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as $\beta$-sitosterol(1), linoleic acid methyl ester(2),1-O-oleoyl-2-O-linoleoyl-3-O-$\beta$-D-galactopyranosyl-sn-glycerol(3), and daucosterol(4). They were the first to be isolated from Canna generalis.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.60-64
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• 2008

The aerial parts of Spathiphyllum cannifolium were extracted with 80% aqueous MeOH and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, three compounds were isolated through the repeated silica gel, ODS, Sephadex LH-20 column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as stigmasterol (1), $(2S)1-O-linolenoyl-2-0-myristoyl-3-0-{\beta}-D-galactopyranosyl-sn-glycerol$ (2) and stigmasterol glucoside (3). They were the first to be isolated from Spathiphyllum cannifolium.

• Journal of Integrative Natural Science
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• v.6 no.1
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• pp.34-38
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• 2013

Tributyltin hydride ($n-Bu_3SnH$), an endocrine disruptor, was slowly polymerized by the group 4 ${Cp^{\prime}}_2TiCl_2/N$-selectride (Cp' = $C_5H_5$, Cp; $Me-C_5H_4$, Me-Cp; $Me_5C_5$, $Cp^*$) catalyst combination to give two phases of products: one is an insoluble cross-linked solid, polystannane in 3-25% yield as minor product via disproportionation/dehydrocoupling combination process, and the other is an oil, hexabutyldistannane in 65-90% yield as major product via simple dehydrocoupling process. Disproportionation/dehydrocoupling process first produced a low-molecular-weight oligostannane possessing partial backbone Sn-H bonds which then underwent an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane. The disproportionation/dehydrocoupling of a tertiary hydrostannane mediated by early transition metallocene/inorganic hydride is quite unusual and applicable.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.624-628
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• 2007

Synthesis of 4-substituted 3-exo-methylenechroman derivatives was carried out by the n-Bu3SnH-mediated vinyl radical cyclization as the key step starting from various salicylaldehydes.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.619-623
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• 2007

Synthesis of 4-substituted 3-exo-methylenechroman derivatives was carried out by the n-Bu3SnH-mediated vinyl radical cyclization as the key step starting from various salicylaldehydes.