• 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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• 제32권5호
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• pp.1554-1558
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• 2011

A novel and efficient method for the synthesis of 2,3-dihydrofurans bearing a variety of substituents on the dihydrofuran ring was achieved by the reaction of cyclic diazodicarbonyl compounds with styrene and vinyl acetate. The key strategy was AgBF$_4$/[Bmim]BF$_4$-catalyzed [3+2] cycloaddition. The synthesized dihydrofurans with an acetate group were further converted to the corresponding 3-acylfurans.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.337-338
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• 1994

• 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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• 제32권1호
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• pp.89-94
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• 2011

The mechanism of the cycloaddition reaction of forming germanic bis-heterocyclic compound between singlet dimethylgermylene carbene and acetone has been investigated with CCSD(T)//B3LYP/6-$31G^*$ method. From the potential energy profile, it can be predicted that, this reaction has one dominant channel. The presented rule of this dominant channel is that the two reactants firstly form a four-membered ring carbene (RC4) through the [2+2] cycloaddition reaction. Due to $sp^2$ hybridization of carbene C atom in RC4, RC4 further combines with acetone to form a reactant complexe (RC5). Due to the further $sp^3$ hybridization of carbene C atom in RC4, RC5 isomerizes to a germanic bisheterocyclic compound (P6) via the transition state (TS5).

• 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.

• Archives of Pharmacal Research
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• 제13권2호
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• pp.126-131
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• 1990

The novel N-phenyl-2-furohydrazonyl chloride 4A and its p-nitro analog 4B have been prepared and identified. The cycloaddition reactions of nitrilimines 5A and 5B, derived by base catalyzed dehydrochlorination of 4A and 4B respectively, to a variety of dipolarophiles were investigated. The results showed that 4A and 4B are usuful precursors for synthesis of differently substituted 3-(2-furyl)-2-pyrazoline derivatives and their pyrazoles and analogs.

• 대한화학회지
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• 제47권4호
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• pp.354-362
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• 2003

Xestoquinone의 퓨란-접합된 4환계화합물에 대한 합성전략을 모델연구를 통하여 조사하였다. 출발물질로서 3-butyn-1-ol을 이용하여, 5-iodo-1-methoxymethoxypentyne(5)이 5단계를 거쳐 제조되었다. Ethyl 2-phenylpropanoate와 5의 반응으로부터 ethyl 7-methoxymethoxy-2-methyl-2-phenyl-5-heptynoate(6)가 88%의 수득율로 얻어졌으며, 6으로부터 중요한 중간체인 methyl 9-oxo-4-methyl-4-phenyl-2,7-nonadiynoate(13)가 6단계를 거쳐 합성되었다. 13의 분자내 고리화반응은 5%의 수득율로 isobenzofuran 14을 생성하였으며, Lewis acid 존재 하에서 4환고리 구조로 전환되었다.

• 약학회지
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• 제44권4호
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• pp.325-333
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• 2000

The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxides 2 with 2-chloroacrylonitrile gave the 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxalines 3, which were converted into the 2,3,4,6-tetrahydro-1H-1,2-diazepino[3,4-b]quinoxalines 5-7. The reaction of compounds 3 with selenium dioxide in acetic acid/water resulted in ring transformation to give the 1,4-dihydro-4-oxopyridazino[3,4-b]quinoxalines 8.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.1021-1022
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• 2002