• Fibers and Polymers
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• v.3 no.3
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• pp.91-96
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• 2002

Polyhydroxyamides derivatized with trifluorormethyl ether and trifluoromethyl ester groups were investigated as possible candidates for a new flame retardant polymer. Model compounds for these derivatized polyhydroxyamides were synthesized and their cyclization chemistry was investigated. The model compound study revealed that trifluorornethyl ester group containing model compounds can cyclize on heating, while trifluoromethyl ether group containing model compounds cannot. The non-fluorinated ether and ether derivatives behaved similarly. The trifluoromethyl ester derivatized polyhydroxyamides were synthesized according to the procedures for the model compounds. TGA characterization revealed that the fluorinated polymers have nearly same thermal stability as the underivatized PHA after cyclization.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.1
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• pp.21-34
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• 2003

Acid amplifiers derived from a certain class of sulfonates suffer from autocatalytic decomposition in the presence of a strong acid to give corresponding sulfonic acid, which catalyze the composition of the parent sulfonates, leading to the liberation of more of the same sulfonic acids in an exponential manner. In this research we synthesized and evaluated 4-hydroxy-4'-(2-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (1), 4,4'-di-(2-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (2), 4-hydroxy-4'-(3-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (3) and 4,4-di-(3-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (4) as novel acid amplifiers with electron withdrawing group. These acid amplifiers (1-4) showed reasonable thermal stability for resist processing temeprature and exhibited higher photosensitivity compared to poly(tert-butyl methacrylate) film without acid amplifiers. Application of acid amplifiers to photofunctional materials, including photoresists, are described as a consequence of the combination of the acid amplifiers with photoacid generator.

• Archives of Pharmacal Research
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• v.24 no.5
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• pp.402-406
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• 2001

Gas chromatographic method was investigated for the chiral separation of several $\beta$-blockeros(atenolol, betaxolol, bisoprolol, metoprolol and pindolol) using (-)-$\alpa$-methoxy-$\alpa$-(trifluoromethyl)phenylacetyl chloride as a chiral derivatizing agent for amino group. Prior to N-acylation, hydroxyl group was converted into O-silyl ethers by react with N-methyl-H-(taimethylsilyl)trifluoroacetamide. The reaction was selective and rapid and the diasteromeric derivatives were well separated by capillary gas chromatography. (R)-isomers were eluted faster than (S)-isomers when (-)-$\alpa$-methoxy-$\alpa$-(trifluoromethyl)phenylacetyl chloride was used as the chiral derivatizing agent. But in the opposite sequence when (+)-$\alpa$-methoxy-$\alpa$-(trifluoromethyl)phenylacetyl chloride was used. No racemization was found during the reaction.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.333-339
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• 1990

A series of new dimesogenic compounds whose mesogens are of aromatic ester or amide type having a trifluoromethyl $(CF_3)$ substituent at the para-position of each terminal phenolic rings were prepared and their liquid crystalline properties were studied by differential scanning calorimetry (DSC) and on a cross-polarizing microscope. The compounds have two identical mesogenic units bracketing a central decamethylene spacer. Trifluoromethyl group appears to favor the formation of smectic phases when it is attached to a phenoxy or anilide terminal. Its group efficiency for mesophase formation seems to be inferior to other common substituents. A thermodynamic analysis of the phase transitions was made and the results were explained in relation to the structures of the compounds.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.64-69
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• 1998

New thirty derivatives of 5,6-dihydro-2-trifluoromethyl-1,4-oxathiin carboxanilide as substrate(S) were synthesized and their fungicidal activities in vivo against rice sheath blight(Rhizoctonia solani) and wheat leaf rust(Puccinia recondita) were examined. The structure activity relationships(SAR) between the activities($pI_{50}$) and a physicochemical parameters of substituents(X) at the phenylcarbamoyl group were analyzed using the adaptive regression analysis method. The 3-methoxy, 11, 3-isopropyloxy, 13 and 3-isopropyl substituent, 25 as X on the phenylcarbamoyl group exhibited the most highest fungicidal activity against the two fungi. The fungicidal potency of the (S) against Puccinia recondita was higher than Rhizoctonia solani. In case of Rhizoctonia solani, the molecular hydrophobicity(${\pi}>0$) and resonance effect(R<0) by meta-alkyl substitutents with electron donating were important factors in determining fungicidal activity. And the HOMO energy(HOMO>0), ABSQ, sum of absolute values of the atomic charges on each atom and specific polarizability(Sp.Pol<0) of (S) were significantly influential towards fungicidal activity against Puccinia recondita.. The interaction between (S) and receptor agonist from the based on SAR studies proceeds through charge-control reaction, and conditions to show higher activity has been also discussed.

• Macromolecular Research
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• v.8 no.4
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• pp.165-171
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• 2000

Fluorinated polyimides with high thermal stability, low optical absorption loss in the optical communication wavelengths of 1.3 and 1.55㎛, and low birefringence and water absorption have been investigated for optical waveguide applications. These polyimides were prepared from 2,2-bis(3,4-dicar-boxyphenyl) hexafluoropropane dianhydride (6FDA) with 1,4-bis-(4-amino-2-trifluoromethyl-phenoxy) tetrafluorobenzene (ATPT) , 1,4-bis-(4-amino-2-trifluoromethyl-phenoxy) benzene (ATPB) , and 1,3-bis-(4-amino-2-trifluoromethyl-phenoxy ) 4,6-dichlorobenzene (ATPD ), respectively. The polyimides obtained had glass transition temperatures that ranged from 260 to 280$\^{C}$, and low water absorption less than 0.4% and low optical loss (> 0.2 dB/cm) at 1.3 and 1.55㎛. Birefringency values of polymer films ranged from 0.0041 to 0.0066.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1218-1220
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• 1999

• Elastomers and Composites
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• v.47 no.4
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• pp.355-363
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• 2012

A series of poly(hydroxyamide)s (PHAs) having trifluoromethyl group were prepared by direct polycondensation of aromatic diimide-dicarboxylic acids with 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane by thionyl chloride and triethyl amine in N-methyl-2-pyrrolidinone (NMP). The PHAs exhibited inherent viscosity in the range of 0.54-0.96 dL/g at $35^{\circ}C$ in DMAc solution. All PHAs were readily soluble in a variety of organic solvents, whereas the polybenzoxazoles (PBOs) were quite insoluble except partially soluble in sulfuric acid. PHAs were converted to PBOs by thermal cycling reaction with heat of endotherm. The maximum weight loss temperature of the PHAs occurred in the range of $559-567^{\circ}C$. The PBOs showed relatively high char yields in the range of 47-59%. Pyrolysis Combustion Flow Calorimeter (PCFC) results of the PBOs showed 12-19 W/g heat release rate (HRR), and 2.7-3.6 kJ/g total heat release (total HR). The HRR of PBO 1 showed the lowest value of 12 W/g, which was 37% lower than that of PBO 3 (19 W/g).

• Bulletin of the Korean Chemical Society
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• v.4 no.5
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• pp.200-203
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• 1983

1,1,1-Trifluoro-4-substituted-3-buten-2-ols and 1,1,1-trifluoro-5-phenyl-4-penten-2-ol were prepared by hydromagnesation and palladium catalyzed phenylation in high stereoselectivity.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.70-76
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• 1996

A series of the herbicidal pyridylsulfonyl areas, none substitutent, 1-(4,6-dimethoxypyrimidine-2-yl)-3-(2-pyridylsulfonyl) urea, 3 and 3-trifluoromethyl substitutent, 1-(4,6-dimethoxypyrimidine-2-yl)-3-(3-trifluoromethyl-2-pyridylsulfonyl) urea, 5(Flazasulfuron) were synthesizied and the rate of hydrolysis of their has been studied in 25%(v/v) aqueous dioxane at $45^{\circ}C$. From the results of solvent effect($m{\ll}1,\;n{\ll}3\;&\;{\mid}m{\mid}{\ll}{\mid}{\ell}{\mid}$), thermodynamic parameter (${\Delta}S^{\neq}=0.54{\sim}\;-2.19\;e.u.\;&\;{\Delta}H^{\neq}=0.025\;Kcal.mol.^{-1}$), hydrolysis product analysis, $pK_a$ constant(3: 4.9 & 5: lit.4.6) and the rate equation, a marked difference in the kinetics of the reaction of 3 and 5(Flazasulfuron) was observed. It may be concluded that the hydrolysis of 5 proceeds through the $A-S_N2Ar$ reaction via conjugate acid$(5H^+)$ below pH 7.0, whereas, above pH 9.0, the hydrolysis proceeds through irreversibly $(E_1)_{anion}$ and reversibly $(E_1CB)_R$ mechanism via conjugate base(CB), respectively. But in case of 5, $A-S_N2Ar,\;(E_1)anion\;and\;(E_1CB)_R$ mechanism involved Smile rearrangement. The mate of rearrangement of 5 to a 3-trifluoromethyl-2-pyridylpyrimidinyl urea(PPU) in acid and 3-trifluoromethyl-2-pyridyl-4.6-dimethoxypyridinyl amine (PPA) in base was increased about 3.5 times by the introduction of trifluoromethyl group in the 3-position on the 2-pyridyl ring. From the basis of these findings, a possible mechanism for the hydrolysis of 5 was proposed and discussed.