• 대한화학회지
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• 제36권4호
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• pp.579-583
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• 1992

5-Bromo-2-methylpent-2-ene(2)을 출발물질로하여 farnesol인 (2E, 6E)-3,7,11-trimethyldodeca-2,6,10-trien-1-ol(1)의 입체 선택적 합성을 수행하였다. 5-Bromo-2-methylpent-2-ene(2)을 요오드화시킨 후, 5-lithio-2,3-dihydrofuran과 반응시켜 5-(4-methylpent-3-enyl)-2,3-dihydrofuran(4)을 얻었다. Dihydrofuran 4를 MeMgI와 Ni(O)-촉매 짝지음 반응시켜 (3E)-4,8-dimethylnona-3,7-dien-1-ol(5)을 72%의 수율로 얻었다. 알릴알코올 5를 4단계로 거쳐 (5E)-6,10-dimethylundeca-5,9-dien-2-one(8)으로 변환시켰다. 화합물 8을 벤젠 용매하에서 dimethylmethoxycarbonylmethylphosponate와 반응시킨 다음, 에탄올 용매하에서 $NaBH_4$로 환원시켜서 (2E, 6E)-3,7,11-trimethyldodeca-2,6,10-tiren-1-ol(1)을 얻었다. Dihydrofuran 4와 MeMgI와의 Ni(O)-촉매 짝지음 반응이 본 연구의 farnsol(1)의 합성에서 중요한 단계이다.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1826-1828
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• 2005

• Bulletin of the Korean Chemical Society
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• 제9권3호
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• pp.176-179
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• 1988

3-Methoxy-4-cyano-2,9-dioxabicyclo[4.3.0]non-3-e ne (1) was prepared by (4 + 2) cycloaddition reaction of methyl ${\alpha}$-cyanoacrylate with 2,3-dihydrofuran. Compound 1 was ring-open polymerized by cationic catalyst such as boron trifluoride etherate to obtain alternating head-to-head (H-H) copolymer (2) of methyl $\alpha$ -cyanoacrylate and 2,3-dihydrofuran. For comparison, head-to-tail (H-T) copolymer (3) was also prepared by free radical copolymerization of the corresponding monomers. The H-H copolymer exhibited minor differences in its $^1H$-NMR and IR spectra, but in the $^{13}C$-NMR spectra significant differences were observed between the H-H and H-T copolymers. All of the H-H and H-T copolymers were soluble in common solvents and the inherent viscosities were in the range 0.2-0.3 dl/g.

• 한국산업융합학회 논문집
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• 제5권4호
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• pp.385-390
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• 2002

An efficient synthesis of spiroannulated dihydrofurans is achieved from 1,3-dicarbonyl compounds and exocyclic alkenes in the presence of cerium ammonium nitrate(IV) in moderate yields. In the case of entries 3-9, as a single product was seen. Especially, reaction of 15 with methylenecyclohexane afforded the two regioisomeric cyclo adducts 21 and 22. The structures of these adducts were confirmed by IR and NMR-Spectra.

• Bulletin of the Korean Chemical Society
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• 제22권10호
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• pp.1156-1158
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• 2001

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.437-438
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• 1993

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2139-2140
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• 2010

• 임산에너지
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• 제20권1호
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• pp.28-34
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• 2001

목재가 셀룰로오스, 헤미셀룰로오스, 리그닌의 주요 3성분이 고분자로 되어 있는 것에 비하여, 추출성분은 분자량이 많아도 1000 정도의 저분자이다. 따라서 목재를 가열할 때 대부분의 추출성분과 주요 3성분이 열분해를 시작하기 전에 휘발되기도 하며, 열분해를 일으켜 소실되기도 한다. 주요 3성분에서 헤미셀룰로오스가 180℃ 전후에서 최초로 열분해를 시작하고 그 다음 셀룰로오스가 240℃에서, 리그닌은 280℃에서 열분해 되기 시작한다. 목재는 열분해 되면서 연기를 발생하는데 이것을 공기 냉각기에 의하여 액화시켜 유출액을 얻을 수 있다. 이 유출액을 장시간 정치하면 두층으로 나뉘게 되는데 상층의 수용성을 목초액, 하층의 비중이 높은 유성물이 타르이다. 기계식 탄화로에서 생산된 침엽수 목초액의 화학성분을 분석한 결과, 목초액의 알코올과 산은 메탄올은 0.12%, 초산은 0.8%로 분석되었으며, 산도는 0.85 이었다. 목초액 특유의 냄새성분으로 다량존재하는 화합물은 furfural, 5-methyl-2-furancarboxyaldehyde, 2,3-pentanedione, 2-butanol, 2,3-dihydrofuran, 1-(2-furanyl)-ethanone, benzaldehyde, 2-furancarboxyaldehyde, 2-methoxyphenol, acetic acid 등이 분석되었다.

• 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.

• 대한화학회지
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• 제58권1호
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• pp.44-48
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• 2014

Catalytic performance of Lewis acids have been investigated in the synthesis of 1,2,3,4-tetrahydroquinolines via cyclocondensation reaction of aniline derivatives with cyclic enol ethers such as 3,4-dihydro-2H-pyran and 2,3-dihydrofuran. The catalytic activity of various of these catalysts in different solvents was compared with other classical catalysts such as KSF clay (1.5 g), $InCl_3$ (10-20 mol%), $ZrOCl_2$ (10 mol%), $Sc(OTf)_3$ (3 mol%), PANI-$InCl_3$ (10 mol%), $I_2$ (20 mol%), $InCl_3$ (5 mol%), 4-npa (25 mol%) and Cellulose-$SO_3H$ (0.03 g).