• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2711-2718
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• 2012

The alkylation of the ambident enolates of a methyl glycinate Schiff base with ethyl chloride was studied at B3LYP and MP2 levels with $6-31+G^*$ basis set. The free (E)-enolates and (Z)-enolate are similar in energy and geometry. The transition states for the alkylation of the free (E)/(Z)-enolate with ethyl chloride have similar energy barriers of ~13 kcal/mol. However, with a lithium ion, the (E)-enolate behaves as an ambident enolate and makes a cyclic lithium-complex in bidentate pattern which is more stable by 11-23 kcal/mol than the (Z)-enolate-lithium complexes. And the TS for the alkylation of (E)-enolate-lithium complex coordinated with one methyl ether is lower in energy than those from (Z)-enolate-lithium complexes by 4.3-7.3 kcal/mol. Further solvation model (SCRF-CPCM) and reaction coordinate (IRC) were studied. This theoretical study suggests that the alkylation of ambident enolates proceeds with stable cyclic bidentate complexes in the presence of metal ion and solvent.

• 한국응용과학기술학회지
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• 제16권2호
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• pp.117-125
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• 1999

The alkylation benzene with 1-dodecene of Mordenite, Zeolite ${\beta}$ and Zeolite Y was studied in the stirring batch reactor. The kinds of zeolites were found to have influenced the reaction conversion and distribution of phenyldodecane isomer in the product. Compared to the alkylation conducted over Zeolite Y and Zeolite ${\beta}$, the alkylation over Mordenite exhibited higher distribution of 2-phenyldodecane and the alkylation conducted over Zeolite Y and Mordenite, the alkylation over Zeolite ${\beta}$ exhibited higher distribution of heavy alkylate which formed through oligomerization reaction readily deactivated the Lewis acid sites. A special feature of the effect of the benzene to 1-dodecene ratio the reaction conversion and selectivity of phenyldodecane isomer was found. At alkylation of benzene with 1-dodecene over Zeolite ${\beta}$, when the catalyst content in the system was high, the reaction will reach the optimal conversion at the higher B/D. When the benzene to 1-dodecene ratio was high, the selectivity of phenyldodecane isomer is high. It was also found that at the similar reaction conversion there was the same product distribution regardless of D/C ratio.

• 폴리머
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• 제38권4호
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• pp.496-501
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• 2014

폴리알파올레핀은 낮은 유동점, 높은 점도지수와 같은 물리화학적 특성이 기존의 광유보다 우수한 합성윤활유이다. 본 논문은 퍼옥사이드계 개시제를 이용하여 올레핀을 사용하지 않고 이소파라핀 분자간의 알킬레이션 반응을 통한 합성 윤활유 제조에 관한 새로운 경로를 제시한다. 평균 탄소수가 i-$C_{16}$, i-$C_{18}$, 그리고 i-$C_{23}$인 세가지 장쇄 이소파라핀의 알킬레이션과 i-$C_{18}$과 2-pentene의 알킬레이션을 di-tert butyl peroxide 라디칼 개시제를 사용하여 여러가지 반응조건에서 수행하여 단독 알킬레이션 반응 경로를 확인하였다. 세가지 유분으로 제조된 알킬레이트를 합성 윤활유로의 적용 가능성을 알아보기 위하여 동점도, 점도지수, 및 유동점을 조사하였다. i-$C_{16}$ 및 i-$C_{18}$ 유분으로 제조된 단독 알킬레이트는 극초고점도지수(>140)와 낮은 유동점(< $-30^{\circ}C$)을 보였다.

• Archives of Pharmacal Research
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• 제15권4호
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• pp.304-308
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• 1992

The alkylation of resorcinol with cyclic allylic alcohol in non-aqueous acid medium gives intermolecular Friedel-Craft compounds. The products are primary alkylation products. The likage always occurs between carbon 3 of cyclic allylic alcohol and the position 2, 4, 5 or 6 of the resorcinol.

• 통합자연과학논문집
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• 제1권3호
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• pp.189-191
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• 2008

Alkylation, carbonylation and cyclization reaction using transition metal(or inner-) complexes as reducing agents or catalysts were investigated.

• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.69-72
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• 2004

The N-alkylation of 4-aminopyrimidine with a tetrahydro-3-aza-cyclopropa[c]inden-5-one, which is a model reaction of the pharmacophore of duocarmycins, was studied with a quantum chemical method. We consider two factors for the acceleration of the N-alkylation; distortion and protonation of the model pharmacophores. The distortion of the spirocyclopropyl moiety in the model spirocyclopropylcyclohexadienone could induce an intrinsic energy of 3-4 kcal/mol, but the protonation on the carbonyl oxygen of the model cyclohexadienone lowers the transition energy of the N-alkylation of 4-aminopyrimidine dramatically (~46 kcal/mol) and is considered to play a major role in the enzyme reaction. The distorted and protonated spirocyclohexadienone is exothermally relieved to a phenol with the heat of reaction of -37 kcal/mol. The protonation process is proposed to be the mode of action of duocarmycins in the DNA alkylation.

• Archives of Pharmacal Research
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• 제21권4호
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• pp.385-390
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• 1998

Adozelesin and carzelesin are synthetic analogues of the extremely potent antitumor antibiotic CC-1065, which alkylates N3 of adenine in a consensus sequence $5^1$-(A/T)(A/T)$A^*$ ($A^*$ is the site of alkylation). We have investigated the DNA sequence selectivity of adozelesin and carzelesin by thermally ind ced DNA strand cleavage assay using radiolabeled restriction DNA fragments. An analysis of alkylation patterns shows that the consensus sequences for carzelesin and adozelesin have been found to be $5^1$-(A/T)(A/T)$A^*$ and $5^1$-(A/F)(G/C)(A/T)$A^*$. A new consensus sequence, $5^1$-(A/T)(A/T)$CA^*$, has been observed to display an additional alkylation site for adozelesin but not for carzelesin. These results indicate that the pattern of sequence selectivity induced by carzelesin is similar but not identical to those induced by adozelosin.

• Bulletin of the Korean Chemical Society
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• 제23권9호
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• pp.1213-1221
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• 2002

Friedel-Crafts alkylation reaction of an isomeric mixture of 1,2,3,4,5,6,7,8- (2) and 1,2,3,4,5,6,7,8-octahydrophenanthrene (2') with excess vinylchlorosilanes such as vinyl(methyl)dichlorosilane (1a) and vinyltrichlorosilane (1b) in the presence of aluminum chloride catalyst at 80 $^{\circ}C$ gives only one dialkylated products, 9,10-bis[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydroanthrenes [(Cl2XSiCH2CH2)2C14H16: X = Me (4a), Cl (4b)] in good yields, but 9,10-bis[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydrophenanthrenes are not obtained. However, monoalkylation of 2 with 1 affords a mixture of both isomeric compounds, 9-[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydroanthracenes 3 and -phenanthrenes 3'. The yield of product 3' is always higher than that of 3. When a mixture of 3 and 3' is alkylated again with 1, only product 4 without phenanthrene type compounds is obtained, indicating that the isomerizations between 2 and 2', or 3 and 3'occur under the alkylation condition. The alkylation with dimethylvinylchlorosilane or trimethylvinylsilane did not proceed. The structure of 4a is determined by X-ray single crystal diffraction analysis.

• 공업화학
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• 제22권6호
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• pp.587-593
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• 2011

대기환경 규제와 자동차 성능 유지 등 고급 가솔린인 알킬레이트 생산공정에 대한 관심이 높아지고 있다. 알킬레이트는 이소부탄과 올레핀의 알킬레이션 반응을 통해서 생산된다. 하지만 기존의 공정에서 사용되고 있는 불산이나 황산의 유해성으로 인하여 새로운 친환경 촉매에 대한 연구가 활발히 진행되고 있다. 최근 기존의 고체산 촉매인 제올라이트 이외에 메조기공 촉매 및 이온성액체를 이용한 연구가 수행되고 있다. 본 논문에서는 이소부탄 알킬레이션 공정을 위한 친환경 촉매에 대한 논하려 한다.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2935-2937
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• 2009

Asymmetric glycolate alkylation reactions in the solid phase were investigated for the first time with good stereoselectivities being obtained by using a Wang resin supported 2-imidazolidinone chiral auxiliary.