• 대한화학회지
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• 제38권1호
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• pp.61-68
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• 1994

Fe(0)촉매하에서 이중고리 생성물이 얻어지는 acetylenic diene을 반응시켜 분자내 [4+2]고리화 첨가반응을 조사하였다. 위 반응은 이분자 첨가반응과 분자내 탄소 고리화 반응이 경쟁적으로 진행된다고 알려져 있다. 그러나 Fe(0)촉매하에서 4,4-dimethyl-3-(tert-butyldimethylsiloxy)-1-phenyl-6,8-decadien-1-yne(11)의 고리화 반응은 단지 이중고리 생성물만이 얻어졌다(수득율 78.1%). 이 결과에서 dienyne의 4,4-위치에 치환된 dimethyl기가 Fe(0)촉매하의 고리화 반응조건에 안정함으로 인하여 분자내 고리화 반응이 촉진되는 것으로 생각된다.

• 대한화학회지
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• 제40권8호
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• pp.11-590
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• 1996

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1305-1308
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• 2010

Regioselective perfluorinated isoxazolidine (5 and 7), isoxazoline (9) and 1,2-addition products (6 and 8) having a long alkyl chain functionality have been prepared by 1,3-dipolar cycloaddition between a 1,3-dipole (NH-nitrone or nitrile oxide) and dipolarophile (perfluoro-2-methyl-2-pentene or styrene), respectively. Interestingly, unusual extended conjugated form of isoxazoline adduct (10) was obtained by dehydrofluorinated reaction from the corresponding perfluorinated isoxazoline adduct (9) which was derived from cycloadition between the perfluorinated long alkyl nitrile oxide 1,3-diplole and styrene olefin. This synthetic methodology of heterocyclic compound having a long alkyl chain functionality is useful for the designing of synthetic strategy and potential self-assembled monolayers (SAM) application. These derivatives were characterized by IR, $^1H$ and $^{19}F$ NMR, and MASS analysis.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.829-837
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• 2002

Recently it was reported that cycloaddition of 6,6-disubstituted cyclohexa-2,4-dienone, 1 with cyclopentadiene gave solely the adduct of type 1.while its reaction with 1,3-cyclohexadiene gave both Ⅱ and Ⅲ. Semiempirical MO calculations were done to elucidate the origin of the selectivity difference between the two dienes. Cycloaddition of 1 with cyclopentadiene is controlled thermodynamically to give only 1-diene adduct by ΔGvalues of 10.6-20.3 kcal/mol, while its reaction with 1,3-cyclohexadiene does not show 1-diene/1-dienophile selectivity due to similar stabilities of the two adducts. Thermodynamic parameters also show that 두애 adducts are more fabourably fromed in the cycloadditions of 1 with both cyclopentadiene and 1,3-cyclohexadiene, which coincides with experimental observations. Cope rearrangements of endo adducts are another avenue to convert between 1-diene and 1-dienophile.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1481-1484
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• 2006

• Journal of Photoscience
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• 제12권3호
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• pp.185-186
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• 2005

The electronic structure of photoskinsensitizing psoralens has been investigated by the ab initio calculations. The photocycloaddition reaction of 8-methoxypsoralen with thymine is studied as a model for the photosensitizing reaction of psoralen with DNA bases. The photocycloadduct was inferred to be a C4-cycloaddition product with the stereochemistry of Syn, H-H, Syn, H-T formed through [2+2] addition reaction between the 3,4-double bonds of 8-methoxypsoralen and 5,6-double bond of thymine base.

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.41-45
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• 1992

Thermal cycloaddition of t-butyl trimethylsilyl thioketone (1) with 2-substituted dienes such as isoprene and 2-trimethylsilyloxy-1,3-butadiene occurred smoothly at 80${\circ}C$ to afford regioiomeric mixtures of cycloadducts. On the other hand, similar treatment of 1 with 1-substituted dienes such as trans-1,3-pentadiene, 1-methoxy-and 1-acetoxy-1,3-butadiene and Danishefsky's diene afforded a single regioisomeric adduct, respectively. Protodesilylation of the silylated adducts 8 and 11 could also be performed with ease.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.362.2-362.2
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• 2002

Antofine belongs to the Phenathroindolizidine group of alkaloids. This natural products exhibit interesting biological properties such as antitumour activity. and anti-inflammentory. Wittig reaction of phenathrenealdehyde with the phosponium salt provided the phenathreneazidealkene in good yield. Intramolecular 1.3-dipolar cycloaddition of the resulting azidealkent in refluxing benzene proceeded the imine. It was reduced with cyanoborohydride of Noyori's Asymmetric Hydrogenation. (omitted)

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.985-987
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• 1996

• 대한화학회지
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• 제30권2호
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• pp.243-247
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• 1986

호모프탈산 무수물(1또는 2)과 디에틸 아조디카르복시산 및 에틸 아릴메티리덴카르밤산과의 고리화첨가반응을 검토하였다. 전자의 반응에서는 2,3--디에톡시카르보닐-2,3-디히드로-1-히드록시프탈라진들(3 및 4)이 생성되었으며, 후자의 반응에서는 3-아릴-4카르복시-2-에톡시카르보닐-3,4-디히드로-1(2H)-이소퀴놀린온들(5~10)이 생성되었다.