- The Pyrethrins and Related Compounds. Part XL - Structure-Activity Relationships of Pyrethroidal Esters with Acyclic Side Chains in the Alcohol Component against Resistant Strains of Housefly (Musca domestica)
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Activities of a range of pyrethroidal esters, incorporating structural variations in all regions of the acid and alcohol components, have been measured against two fully characterised and homozygous resistant strains of Musca domestica L. (kdr and super-kdr). The results, limited in this paper to esters of alcohols with acyclic side chains, show the same level of uniform resistance to the kdr strain observed previously, across a range of acid and alcohol variations. Against the super-kdr strain, in contrast to the cyclic side chain set, resistance factors are barely higher than for the kdr strain. Against super-kdr flies, some dependence of resistance factor on the position of the side chain substituent was detected. Polyfluorobenzyl esters confer particularly low resistance factors.
- Farnham, Andrew W.,Khambay, Bhupinder P. S.
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Read Online
- Synthetic method of transfluthrin intermediate
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The invention discloses a synthetic method of a transfluthrin intermediate, and belongs to the technical field of chemical synthesis, the synthetic method is characterized by comprising the following steps: (1) taking 2, 3, 5, 6-tetrafluorobenzene as a raw material, and reacting with carbon tetrachloride to obtain 2, 3, 5, 6-tetrafluorotrichloromethyl benzene; (2) under the action of a composite catalyst, carrying out catalytic hydrolysis on the 2, 3, 5, 6-tetrafluorotrichloromethyl benzene to obtain 2, 3, 5, 6-tetrafluorobenzoyl chloride; (3) under the action of a catalyst, the 2, 3, 5, 6-tetrafluorobenzoyl chloride and hydrogen are subjected to a Rosenmonde reduction reaction, and 2, 3, 5, 6-tetrafluorobenzaldehyde is obtained; (4) carrying out catalytic hydrogenation reaction on the 2, 3, 5, 6-tetrafluorobenzaldehyde and hydrogen to obtain 2, 3, 5, 6-tetrafluorobenzyl alcohol; the method has the advantages of simple steps, high yield of each step and simple reaction; the reaction conditions of each step are mild, and the method has the advantages of low cost, high yield and easily available reaction conditions.
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Paragraph 0047; 0055-0056; 0057; 0065-0066; 0067; ...
(2021/08/25)
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- Direct evidence of edge-to-face CH/π interaction for PAR-1 thrombin receptor activation
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Heptapeptide SFLLRNP is a receptor–tethered ligand of protease-activated receptor 1 (PAR-1), and its Phe at position 2 is essential for the aggregation of human platelets. To validate the structural elements of the Phe-phenyl group in receptor activation, we have synthesized a complete set of S/Phe/LLRNP peptides comprising different series of fluorophenylalanine isomers (Fn)Phe, where n = 1, 2, 3, and 5. Phe-2-phenyl was strongly suggested to be involved in the edge-to-face CH/π interaction with the receptor aromatic group. In the present study, to prove this receptor interaction definitively, we synthesized another series of peptide analogs containing (F4)Phe-isomers, with the phenyl group of each isomer possessing only one hydrogen atom at the ortho, meta, or para position. When the peptides were assayed for their platelet aggregation activity, S/(2,3,4,6-F4)Phe/LLRNP and S/(2,3,4,5-F4)Phe/LLRNP exhibited noticeable activity (34% and 6% intensities of the native peptide, respectively), whereas S/(2,3,5,6-F4)Phe/LLRNP was completely inactive. The results indicated that, at the ortho and meta positions but not at the para position, benzene-hydrogen atoms are required for the CH/π interaction to activate the receptor. The results provided a decisive evidence of the molecular recognition property of Phe, the phenyl benzene-hydrogen atom of which participates directly in the interaction with the receptor aromatic π plane.
- Asai, Daisuke,Inoue, Naoko,Sugiyama, Makiko,Fujita, Tsugumi,Matsuyama, Yutaka,Liu, Xiaohui,Matsushima, Ayami,Nose, Takeru,Costa, Tommaso,Shimohigashi, Yasuyuki
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- A substituted aromatic alcohols of the economical efficiency of the synthesis process (by machine translation)
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The invention discloses a substituted aromatic alcohols of the economical efficiency of the synthesis process, the COOR1 - C6 F4 - COOR1 (R1 Representative C1 - C4 Alkyl) to the organic solvent in the input, in the NaBH4 Under the action of the shall CH reduction reaction2 OH - C6 F4 - CH2 OH (II) and CH2 OH - C6 F4 - COOH (III); the mixture is dissolved in a weak acid buffer solution, after adjusting the pH of the extraction, the aqueous layer containing in II, III contained in the oil reservoir; the oil reservoir into the non-protic solvent removes the carboxyl, shall be CH2 OH - C6 HF4 . The present invention, reduction process residence in the intermediate state, the process on the reduction reducing the requirements of the complete degree, reduce the used as the reducing agent; the mixture with chemical separation, the product is very good use can be obtained. (by machine translation)
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Paragraph 0029; 0033; 0034; 0037; 0038; 0042
(2019/05/15)
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- Preparation method of tetrafluorobenzene methanol
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Belonging to the technical field of organic synthesis, the invention discloses a preparation method of tetrafluorobenzene methanol. The method includes: reacting tetrafluorobenzoic acid with thionyl chloride to produce tetrafluorobenzoyl chloride, then taking tetrafluorobenzoyl chloride as the raw material, and conducting reduction in water with sodium borohydride activated by an ether solvent toobtain tetrafluorobenzene methanol. According to the invention, the ether solvent and sodium borohydride are subjected to complexing to activate sodium borohydride, water is adopted as the solvent forreduction, the reaction yield is high, the reductant sodium borohydride can complete the reaction at a catalytic amount, and the reaction process is greener and more environmentally friendly.
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Paragraph 0035; 0037-0046
(2019/02/13)
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- Tetrafluorobenzyl alcohol producing mechanical device
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The present invention discloses a tetrafluorobenzyl alcohol producing mechanical device and belongs to the machinery field of fine chemical engineering production. The mechanical device comprises: a chemical reacting kettle (1), a decolorizing kettle (2), a distilling kettle (3), and a dryer (4). The mechanical device is characterized in that a 2,3,5,6-tetrafluoro-benzoic acid inlet (5), an ethylene glycol dimethyl ether inlet (6), an ethylene glycol dimethyl ether solution inlet of sodium borohydride (7), and an ethylene glycol dimethyl ether solution inlet of sulfate dimethyl ether (8). A first material pulp pump and a pipeline (9) are arranged between the chemical reacting kettle (1) and the decolorizing kettle (2). An activated carbon inlet (10) is arranged on the decolorizing kettle (2). A second material pulp pump and a pipeline (11) are arranged between the decolorizing kettle (2) and the distilling kettle (3). A steam outlet (12) is arranged on distilling kettle (3). A second conveyor (13) is arranged between the distilling kettle (3) and the dryer (4). A finished product outlet (14) is arranged on the dryer (4).
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Paragraph 0011; 0012; 0013
(2017/06/23)
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- Mg-Prompted Polyfluoroarene C-H Functionalization: Formal Synthesis of Transfluthrin, Fenfluthrin, and Tefluthrin
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Directing group and transition metal free C-H bond functionalization of a simple molecule is an ideal but challenging chemical transformation. Herein, we report a general Mg-prompted approach to synthesize versatile polyfluoroaryl carbinols at ambient temperature via polyfluoroarene C-H bond addition to aldehydes, which featured excellent monoaddition selectivity and broad functional group compatibility. The usefulness of this practical and efficient method was demonstrated in gram-scale formal synthesis of pyrethroid insecticides transfluthrin, tefluthrin, and fenfluthrin.
- Jia, Xuejiao,Wang, Junya,Ding, Xue,Yang, Jun,Li, Nan,Zhao, Na,Huang, Zhiyan
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p. 10874 - 10882
(2015/11/18)
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- A new synthetic route to polyfluorobenzyl alcohol
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The synthesis of polyfluorinated benzyl alcohol from pentafluorobenzoic acid has been developed. An economical and effective direct reduction method of polyfluorobenzoic acid by zinc borohydride is described.
- Zhang, Deyan,Chen, Zizhan,Cai, Huihua,Zou, Xinzhuo
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experimental part
p. 938 - 941
(2010/01/15)
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- Process for producing tetrafluorobenzenemethanols
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The present invention relates to a process by a series of reactions using tetrafluorocyanobenzens as material for producing tetrafluorobenzenemethanols, tetrafluorobenzenecarbaldehyde dialkylacetals and tetrafluorobenzenecarbaldehydes in a high purity and a high yield which are useful as intermediates in the production of cyclopropanecarboxylic acid esters having insecticidal action, and also relates to a novel tetrafluorobenzenecarbaldehyde dimethylacetal.
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- PROCESS FOR PRODUCING TETRAFLUORO BENZENEMETHANOLS
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The present invention relates to a process by a series of reactions using tetrafluorocyanobenzens as material for producing tetrafluorobenzenemethanols, tetrafluorobenzenecarbaldehyde dialkylacetals and tetrafluorobenzenecarbaldehydes in a high purity and a high yield which are useful as intermediates in the production of cyclopropanecarboxylic acid esters having insecticidal action, and also relates to a novel tetrafluorobenzenecarbaldehyde dimethylacetal.
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- Process for producing cyclopropanecarboxylates
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There is disclosed a process process for producing a cyclopropanecarboxylate of formula (1): 1which process comprises reacting cyclopropanecarboxylic acid of formula (2): 2with a monohydroxy compound of formula (3): R6OH??(3),in the presence of a catalyst compound comprising an element of to Group 4 of the Periodic Table of Elements.
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- Process for production of benzonitrile and benzyl alcohol
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PCT No. PCT/JP97/03037 Sec. 371 Date Apr. 27, 1998 Sec. 102(e) Date Apr. 27, 1998 PCT Filed Aug. 29, 1997 PCT Pub. No. WO98/08795 PCT Pub. Date Mar. 5, 1998A process for producing a fluorinated benzonitrile comprising hydrogenolyzing a fluorinated dicyanobenzene substituted with 1 to 4 fluorine atoms and having the remainder which may be substituted with a chlorine atom in the presence of a catalyst to cause hydrodecyanation of only the cyano group of one side and a process for producing a fluorinated benzyl alcohol comprising reducing the fluorinated benzonitrile and hydrolyzing the fluorinated benzonitrile and reducing the resultant corresponding fluorinated benzoic acid to convert the cyano group to a hydroxymethyl group.
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- Ester compounds
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An ester compound represented by the formula: wherein R is a hydrogen atom, a C1-C3 alkyl group unsubstituted or substituted with one or more halogen atoms, an allyl group unsubstituted or substituted with one or more halogen atoms, or a propargyl group unsubstituted or substituted with one or more halogen atoms; and X is a hydrogen atom, a halogen atom, a C1-C3 alkyl group unsubstituted or substituted with one or more halogen atoms, a C2-C3 alkenyl group unsubstituted or substituted with one or more halogen atoms, a C2-C3 alkynyl group unsubstituted or substituted with one or more halogen atoms, a C1-C3 alkoxy group unsubstituted or substituted with one or more halogen atoms, a C1-C3 alkylthio group unsubstituted or substituted with one or more halogen atoms, or a C1-C3 alkoxymethyl group containing a C1-C3 alkoxy group unsubstituted or substituted with one or more halogen atoms, has an excellent pest-controlling effect.
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- Reductive dehalogenation of polyfluoroarenes by zinc in aqueous ammonia
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Aqueous ammonia has been found to be a good and versatile medium for the highly selective hydrodehalogenation of polyfluoroarenes by zinc under unprecedentedly mild conditions. The reduction of pentafluorobenzoic acid, 2,3,4,5,6-pentafluorobenzyl alcohol, pentafluorobenzamide, pentafluoropyridine, heptafluoro-2-naphthoic acid, 1,3,4,5,7,8-hexafluoro-2-naphthoic acid, octafluoronaphthalene, octafluorotoluene, decafluorobiphenyl, chloropentafluorobenzene and 4-chlorotetrafluorobenzoic acid give products derived from the removal of one or two halogen atoms. A reduction mechanism, proceeding through electron capture to give a radical anion and then fragmentation of the latter, has been suggested. The observed high selectivity of the process suggests a radical anion formed by direct electron transfer from zinc to substrate. The dehalogenation regioselectivity is basically in accordance with that expected for radical anion fragmentation.
- Laev, Sergey S.,Shteingarts, Vitalii D.
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p. 175 - 185
(2007/10/03)
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- Reductive defluorination of polyfluoroarenes by zinc in aqueous ammonia
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Aqueous ammonia has been found to be a good and versatile medium for the reductive defluorination of polyfluoroarenes by zinc. Upon the reduction of pentafluorobenzoic acid, 2,3,4,5,6-pentafluorobenzyl alcohol, pentafluoropyridine and heptafluoro-2-naphthoic acid individual products derived from the removal of one fluorine atom have been obtained.
- Laev, Sergey S.,Shteingarts, Vitalij D.
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p. 3765 - 3768
(2007/10/03)
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- Photosubstitution reactions on aromatic and heteroaromatic rings evidence for addition and substitution mechanism
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Irradiation of a cyclohexane solution of hexafluorobenzene in the presence of benzophenone resulted in both, substitution and addition products. Similar photoreaction has been observed by irradiation of hexafluorobenzene in some alcohols in the presence of benzophenone. The reaction of pentafluorobenzene with methanol or cyclohexane resulted in the substitution of a 2-or 4-fluoro atom, while the reaction of pentafluoroanisole resulted in the formation of o-, m- and p-isomers. Irradiation of a cyclohexane solution or of an alcohol solution of octafluoronaphthalene yielded 1- and 2-substituted products. On the other hand, the photosubstitution of fluorine atom in pentafluoropyridine took place exclusively at the position four, thus forming 4-cyclohexyl or 4-(1-hydroxyalkyl) substituted products.
- Sket, Boris,Zupan, Marko,Zupancic, Natasa,Pahor, Barbara
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p. 5029 - 5042
(2007/10/02)
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