• Analytical Science and Technology
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• v.7 no.3
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• pp.321-327
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• 1994

The mild thermal decomposition of 7, 7-dimethyl-1, 2, 3, 4, 5-pentaphenyl-7-silanorbornadiene with excess methyl alcohol proceeds to give 1-methoxydimethylsilyl-1, 2, 3, 4, 6-pentaphenylcyclohexa-2, 5-diene which is colorless needle crystal. The cophotolysis of the solution of 7-silanorbornadiene in the excess ethyl alcohol proceeds with loss of silylenes to give ethoxydimethylsilane which is insertion reaction product of silylene with O-H bond of ethyl alcohol. According to above results, it is presumed that the mechanism of photochemical decomposition and that of mild thermochemical decomposition of 7-silanorbornadiene are different.

• Journal of Photoscience
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• v.1 no.2
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• pp.119-122
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• 1994

$PdCI_2(PPh_3)_2$-catalyzed photolysis of 1-phenyl-4-(pentamethyldisilanyl)buta-1,3-diyne (1) in dry benzene gives 1,4-disilacyclohexa-2,5-diene type dimerization products(3-6) via silacyclopropene. The silacyclopropene is formed from the singlet excited state of 1 and this silacyclopropene reacts with $(PPh_3)_2Pd^0$to form palladasilacyclobutene. In this reaction, the silylene-palladium complex is generated and reacts with 1 to give another silacyclopropene. $PdCI_2(PPh_3)_2$catalyzed photolysis of 1 with other alkynes supports the involvement of this silylene complex.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1103-1107
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• 1994

Interaction of triethylsilane and diphenylsilane ($Ph_2$$SiH_2$, $Ph_2$$SiD_2$) with the surfaces of rhodium has been examined by trapping the reaction intermediates with 2,3-dimethyl-l,3-butadiene. 1,4-Hydrosilylation of the diene is predominantly observed to occur under mild condition over the rhodium catalyst. It is inferred from the product analyses that silylene and silyl radicals bonded to rhodium surfaces are the intermediates for addition of silylene to the diene, and for 1,4-hydrosilylation, respectively.

• Journal of the Korean Chemical Society
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• v.60 no.2
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• pp.149-153
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• 2016

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.65-65
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• 1987

• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.460-465
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• 1994

New silicon-monosubstituted (${\eta}^4$-2,3,4,5-tetraphenyl-l-silacyclopentadiene)transi tion metal complexes are described. (7-Alkyl-7-silanorbornadienyl)MLn(Alkyl=Methyl: MLn=CpRu$(CO)_2$: Alkyl=Methyl: MLn=CpNi(CO): Alkyl=Ethyl: MLn=CpNi(CO)) complexes were prepared from the corresponding silole-transition metal complexes with dimethylacetylenedicarboxylate. Cycloaddition products were obtained with 2,3-dimethyl-1,3-butadiene, 2,3-butanedione, and 1,4-benzoquinone through the ruthenium-substituted silylene. We have determined the crystal structure of (1-methyl-2,3,4,5-tetraphenyl-l-silacyclopentadien yl)cyclopentadienyldicarbonylruthenium by using graphite monochromated Mo-Ka radiation. The compound was crystallized in the monoclinic space group $P2_{1/c}$ with a = 9.838(l), b = 15.972(3), c = 18.327(3) ${\AA}$, and ${\beta}= 94.28(l)^{circ}$. The ruthenium moiety CpRu$(CO)_2$ on silicon is in an axial position.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.223-223
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• 2006

A Suzuki-coupling route is developed for preparation of ortho-phenylene-bridged Cp/amido complexes, one of which shows higher activity, higher 1-hexene incorporation, and higher molecular weight than the silylene-bridged standard CGC $[Me_{2}Si({\eta}^{5}-Me_{4}Cp)(N^{t}Bu)]TiCl_{2}$.

• Journal of the Korean Chemical Society
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• v.64 no.4
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• pp.231-235
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• 2020

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1349-1354
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• 2010

The geometries and isomerization of the alkylidene silylenoid $H_2C$ = SiLiF as well as its insertion reactions with R-H (R = F, OH, $NH_2$) have been systematically investigated at the B3LYP/6-311+$G^*$ level of theory. The potential barriers of the three insertion reactions are 97.5, 103.3, and 126.1 kJ/mol, respectively. Here, all the mechanisms of the three reactions are identical to each other, i.e., an intermediate has been formed first during the insertion reaction. Then, the intermediate could dissociate into the substituted silylene ($H_2C$ = SiHR) and LiF with a barrier corresponding to their respective dissociation energies. Correspondingly, the reaction energies for the three reactions are -36.4, -24.3, and 3.7 kJ/mol, respectively. Compared with the insertion reaction of $H_2C$ = Si: and R-H (R = F, OH and $NH_2$), the introduction of LiF makes the insertion reaction occur more easily. Furthermore, the effects of halogen (F, Cl, Br) substitution and inorganic salts employed on the reaction activity have also been discussed. As a result, the relative reactivity among the three insertion reactions should be as follows: H-F > H-OH > H-$NH_2$.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.757-764
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• 1993

The photochemical precursors, 1,1,1,3,3,3-hexamethyl-2-phenyltrisilane(2) and 2,3-dicarbomethoxy-1,4,5,6,7-pentaphenyl-7-silanorbornadiene(5) were synthesized in the yield of 10% and 73%, respectively. Irradiation of 2 at 254 nm in the presence of triethylsilane gave 1,1,1-triethyl-2-phenyldisilane (6) in 44% yield which was the product of phenylsilylene insertion into the Si-H bond. Irradiation of 2 in the presence of diphenylacetylene gave 1-phenyl-1-silacyclopenta-2,4-diene(4) in 68% yield together with 1,2-diphenyl-1,2-disilacyclohexa-2,5-diene(26%) which were formed from [2＋2] addition of the silacyclopropene to diphenylacethylene and formed from dimerization of silacyclopropene, respectively. From the neat photolysis of precursor 2,1,5-dihydrosilanthrene(11), intermolecular C-H insertion product of phenylsilylene and 1,2-diphenyltrisilane(12), Si-H insertion product of phenylsilylene to the precursor were obtained in the yield of 5% and 7%, respectively. In the same experimental condition, both photolyses of 5 in the presence of triethylsilane and methanol showed that the intramolecular 1,5-sigmatropic rearrangement of precursor 5 to give the formation of silylenolether was more favorable process than the generation of phenylsilylene.