• Bulletin of the Korean Chemical Society
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• 제23권2호
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• pp.337-345
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• 2002

The equilibrium structures for the ground and transition states of $C_7H_7^+$ isomers have been investigated using sophisticated ab initio quantum mechanical techniques with various basis sets. The structures of tropyrium and benzyl cations have been fully optimized at the DZP CCSD(T) levels of theory. And the structures of o-, m-and p-tolyl cations are optimized fully up to the DZ CCSD(T) levels of theory. The geometries for the transition states between three isomers of tolyl cations have been optimized up to DZP CISD level of theory. The SCF harmonic vibrational frequencies for tropylium, benzyl, and three isomers of tolyl cations are all real numbers, which confirm the potential minima and each unique imaginary vibrational frequencies for TS1 and TS2 confirm the true transition states. The relative energy of the benzyl cation with respect to the tropyrium cation is predicted to be 28.5 kJ/mol and is in good agreement with the previous theoretical predictions. The 0 K heats of formation, ${\Delta}H^{\circ}_{f0}$, have been predicted to be 890, 1095, 1101, and 1110 kJ/mol for tropylium, ortho-, meta-, and para-tolyl cations by taking the experimental value of 919 kJ/mol for the benzyl cation as the base level. The relative stability between tolyl cations is in the order of ortho

• 대한화학회지
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• 제8권4호
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• pp.153-157
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• 1964

Chloromethylation, malonic ester 합성법 및 decarboxylation에 의한 중간체들을 거친 tert.-butyl ${\beta}$-(o-tolyl)-perpropionate 치환체들의 합성을 기술하였다. 심하지 않은 치환기효과를 나타내는 bromo-, chloro- 및 methyl- 기를 가진 중간체들은 좋은 수율로 얻어져서 목적한 바 과산화 ester들을 얻었으나 nitro기를 가진 중간체는 극히 적은 수율로 얻어졌고 한편 센 electron donating effect를 나타내는 group로 치환된 toluene들의 chloromethylation은 polymerize하는 결과를 가져왔다.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.299-301
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• 2006

• 대한화학회지
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• 제54권1호
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• pp.59-64
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• 2010

일련의 불소화된 티아디아졸 3, 트리아졸 4, 그리고 옥사디아졸 5이 (2-(6-Methyl-2-P-tolyl-lH-imidazo[1,2-a]pyridin-3-yl)핵종을 가지고 있는 티오세미카르바지드로 부터 합성되어진다. 초음파조사 방법 뿐만 아니라 일반적인 방법에 의해 반응이 진행되었다. 모든 생성물들은 IR, 1H NMR, MS로 구조가 결정되었고, 이들 화합물의 항균활성을 스크닝하였다.

• 한국광과학회:학술대회논문집
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• 한국광과학회 1996년도 학술대회지
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• pp.43-43
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• 1996

• Bulletin of the Korean Chemical Society
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• 제18권4호
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• pp.439-441
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• 1997

• Bulletin of the Korean Chemical Society
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• 제16권6호
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• pp.470-472
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• 1995

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.719-728
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• 2005

A novel 2-amino-4-(8-quinolinol-5-yl)-1- (p-tolyl)-pyrrole-3-cabonitrile (2) was obtained by the reaction of 2-[2-bromo-1-(8-hydroxyquinolin-5-yl)-ethylidene]-malononitrile (1) with p-toluidene. The new synthon compound (2) could be annelated to the corresponding pyrrolo[2,3-d]pyrimidines (4, 6, 7, 26-28), triazolo[1,5-c]pyrrolo[3,2-e]pyrimidines (10, 29, 30), pyrrolo[2,3-c]pyrazoles (11-15), pyrrolo[1,2-a]pyrrolo[3,2-e] pyrimidine (17) and imidazo[1,2-c]pyrrolo[3,2-e]pyrimidines (18-25) via the reaction with some reagents such as acetic anhydride, formamide, triethyl orthoformate, hydrazine hydrate, hydroxylamine, ethylenediamine, carbon disulfide and phosphorus oxychloride. Chemical and spectroscopic evidences for the structures of these compounds are presented. The antifungal and antibacterial activity of the newly synthesized comounds were evaluated.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1335-1338
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• 2005

Thianthrene cation radical perchlorate ($Th^{+{{\cdot}}}{ClO_4}^-$) reacted readily with two isomeric thiols, benzylthiol (1) and 4-methylbenzenethiol (7) in an acetonitrile solution at room temperature. From the reaction of 1, the major products, N-benzylacetamide (4) and benzyl sulfide (5), are characteristic of benzyl carbocations while the minor one, benzyl disulfide (6) implies free radical component of the reaction. It is unprecedented that the formation of a benzyl carbocation was caused by the extrusion of sulfur atoms from benzyl sulfur cations (3). In contrast, from the reaction of 7, only p-tolyl disulfide (10) was obtained from both sulfur radicals and cations. In the reaction of 7 the thio-extrusion was not observed from the p-tolyl sulfur cation (9). A thianthrene cation radical ($Th^{+{{\cdot}}}$) was reduced quantitatively to thianthrene (Th) in both reactions.

• Journal of Photoscience
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• 제9권1호
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• pp.13-15
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• 2002

The structurally rigid $\alpha$-(o-alkylphenyl) acetophenone derivatives lacking $\beta$-hydrogens, 3,3-dimethyl-2-o-tolylibdan-1-one and 2-o-tolyl-benzofuran-3-one, were prepared and their photochemical behaviors were examined. The former did not give any photoproduct while the latter turned into its enol tautomer. The difference of reactivity of two ketones was attributed to aromatic character of the extol of the benzofuranone. It was concluded that the reaction occurred via photoinduced 1,3-H transfer.