• 공업화학
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• 제21권3호
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• pp.278-283
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• 2010

폭발성기를 가진 azido기($-CH_2N_3$), nitrato기($-CH_2ONO_2$) 그리고 hydrazino기(-$CH_2N_2H_3$)로 치환된 옥소란 고폭 화약류의 산 촉매 하에서 중합반응을 반경험적인 MINDO/3, MNDO, AM1 방법 등을 사용하여 이론적으로 고찰하였다. 옥소란 고폭 화약류의 친핵성 및 염기성은 옥소란 산소원자의 음전하크기로 설명할 수 있고, 중합하의 성장단계에서 옥소란의 반응성은 옥소란의 반응중심 탄소원자의 양전하크기와 친전자체의 낮은 LUMO 에너지에 좌우됨을 알 수 있다. 옥소란 고폭 화약류의 고리형 oxonium 이온형이 열린 carbenium 이온형으로 전환되는 과정은 oxonium 이온과 carbenium 이온 사이의 계산된 안정화 에너지(17.950~30.197 kcal/mol)에 의하면 carbenium 이온이 더 유리함을 예측 할 수 있다. 평형상태의 고리형 oxonium 이온과 열린 carbenium 이온의 농도 크기가 반응 메카니즘의 결정단계이며, 산 촉매 하의 형태와 계산을 기초로 하여 빠른 평형을 예상하여 볼 때 선폴리머(prepolymer) 성장단계에서 $S_N1$ 메카니즘이 $S_N2$ 메카니즘보다 빠르게 반응 할 것으로 예측된다.

• Bulletin of the Korean Chemical Society
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• 제20권10호
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• pp.1195-1199
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• 1999

2-(2,4,5-Trimethoxyphenyl)-4-methylene-1,3-dioxolane (1b), 2-(2,4,6-trimethoxyphenyl)-4-methylene-1,3-di-oxolane (2b), and 2-(3,4,5-trimethoxyphenyl)-4-methylene-1,3-dioxolane (3b) were prepared and polymerized with boron trifluoride. Boron trifluoride catalyzed reaction proceeded via mainly ring-opening polymerization and cyclization reaction to yield poly(keto ether) and 3(2H)-dihydrofuranone. The yields of polymer and cyclized product exhibited a dependency on the position of the methoxy substituents in the benzene ring of 2-phenyl-4-methylene-1,3-dioxolane derivatives. Electrophilic attack of methylene or oxygen atom on 4-meth-ylene-1,3-dioxolane ring were suggested for the polymerization and cyclization.

• 한국결정학회지
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• 제11권1호
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• pp.22-27
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• 2000

The structure of cis-(malonato)[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II) with a potent anticancer activity has been determined by the X-ray crystallographic method. Crystal data are as follows: Pt(C/sub 11/H/sub 20/N₂O/sub 6/), M/sub 4/=471.38, monoclinic, P2₁, a=7.112(1), b=33.615(3), c=7.135(1)Å, β=116.80(1)°, V=1522.6(3)Å, and Z=4. The two independent molecules with very similar structures are approximately related by pseudo two-fold screw axis symmetry, which makes the monolinic cell look like the orthorhombic cell with one molecule in the asymmetric unit and space group C222₁. The crystal packing mode is similar to that of the analogue with the dimethyl substituents instead of the isopropyl group. The Pt atom is coordinate to two O and two N atoms in a square planar structure. The six-membered chelate ring in the leaving ligand assumes a conformation intermediate between the half chair and the boat forms. The seven-membered ring in the carrier ligand assumes a twist-chair conformation and the oxolane ring assumes an envelope conformation. Crystal packing consists of the extensive hydrogen-bonding network in the two-dimensional molecular layers and weak van der Waals interactions between these layers.