Abstract:
A process for the preparation of chlorofluoronitrobenzenes and difluoronitrobenzenes, which comprises heating dichloronitrobenzene to not more than 200.degree. C. in excess with an alkali metal fluoride having a total water content of about 0.2 to about 2.5% by weight in the presence of a quaternary ammonium and/or phosphonium salt, crown ether and/or polyethylene glycol dimethyl ether as catalyst in the absence of a solvent.
Abstract:
This invention relates to a novel thermoplastic and amorphous polyimide which is readily soluble in organic solvent, a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the thermoplastic polyimide and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition, a polyimide-based composite obtained by molding the above soluble and thermoplastic polyimide in combination with a fibrous reinforcement, and a fibrous reinforcement having a surface modified with the above polyimide.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein m and n are individually an integer of 0 or 1, and R is ##STR2## The polyimide of the invention is essentially amorphous, excellent in melt flow stability in the decreased temperature as compared with conventionally known polyimide and has greatly improved processability.The polyimide of the invention obtained by using a novel aromatic diamino compound as a monomer can control various properties such as melt flow ability and solubility in solvents by side chains and not by principal chain of polyimide. Thus, excellent melt flow property and solubility in solvents can be obtained while maintaining high heat resistance and adhesive property which are derived from benzophenone structure of the diamino compound of the the invention.
Abstract:
A nonsolvent process of synthesizing bis(2,2-dinitropropyl)formal (BDNPF) is disclosed. In the process, 2,2-dinitropropanol (DNPOH) is reacted at low temperature with a formaldehyde source in the presence of a protic acid catalyst, such as H.sub.2 SO.sub.4, HCl, H.sub.3 PO.sub.4, or HBr. To inhibit byproduct formation, the reaction temperature is maintained from about -30.degree. C. to 30.degree. C. Upon completion of the reaction, the reaction solution is quenched with water and washed with an aqueous hydroxide ion solution. The hydroxide ion concentration should be sufficient to neutralize the protic acid catalyst during the quenching step and to solubilize unreacted 2,2-dinitropropanol as well as other aqueous soluble byproducts in the reaction solution. The BDNPF product is extracted with a low boiling temperature polar organic solvent, such as methyl tert-butyl ether (MTBE) or equivalent solvent. The organic solvent is evaporated to yield usable BDNPF product. The resulting yield is at least 60% based on the starting quantity of 2,2-dinitropropanol.
Abstract translation:公开了合成双(2,2-二硝基丙基)甲醛(BDNPF)的非溶剂方法。 在此过程中,在质子酸催化剂如H 2 SO 4,HCl,H 3 PO 4或HBr存在下,将2,2-二硝基丙醇(DNPOH)在低温下与甲醛源反应。 为了抑制副产物形成,将反应温度保持在约-30℃至30℃。反应完成后,将反应溶液用水淬灭并用氢氧化钠水溶液洗涤。 氢氧根离子浓度应足以在淬火步骤期间中和质子酸催化剂,并将未反应的2,2-二硝基丙醇以及其它水溶性副产物溶解在反应溶液中。 BDNPF产物用低沸点极性有机溶剂如甲基叔丁基醚(MTBE)或等效溶剂萃取。 将有机溶剂蒸发,得到可用的BDNPF产物。 基于2,2-二硝基丙醇的起始量,所得产率为至少60%。
Abstract:
Process for producing 5-alkoxy-2,4-dinitroalkylbenzenes of the general formula (I) ##STR1## R.sup.1 =C.sub.1 to C.sub.4 alkyl; R=C.sub.1 to C.sub.6 alkyl group, C.sub.2 to C.sub.4 hydroxyalkyl, C.sub.3 to C.sub.4 dihydroxyalkyl,in which a 3-fluoroalkylbenzene is nitrated and the obtained 2,4-dinitro-5-fluoroalkylbenzene is then reacted with a suitable alcohol at -5.degree. C. to +25.degree. C. with the addition of sodium hydroxide or potassium hydroxide.
Abstract:
Process for preparing aromatic olefins of the formula (1) ##STR1## in which R.sup.1 -R.sup.3 are hydrogen, alkyl (C.sub.1 -C.sub.8) , alkoxy-(C.sub.1 -C.sub.5), phenyl, fluorine, chlorine, bromine, --OH, --NO.sub.2, --CN, --CHO, --COalkyl(C.sub.1 -C.sub.4) , --COphenyl, --COOalkyl (C.sub.1 -C.sub.4) , --OCOalkyl(C.sub.1 -C.sub.4), --NHCOalkyl(C.sub.1 -C.sub.4) , --CF.sub.3, --NH.sub.2, --NH--alkyl(C.sub.1 -C.sub.4) or --N(alkyl(C.sub.1 -C.sub.4)).sub.2 and R.sup.4 is hydrogen, alkyl(C.sub.1 -C.sub.8), phenyl, fluorine, chlorine, bromine, --OH, --NO.sub.2, --CN, --CHO or --OCOalkyl (C.sub.1 -C.sub.4) , and X is, inter alia, alkenyl(C.sub.2 -C.sub.12) or cycloalkenyl(C.sub.4 -C.sub.8) or the group ##STR2## in which R.sup.5 and R.sup.6 are, independently of one another, hydrogen or methyl, and Y is --phenyl, --CN, --COOH, --COOalkyl(C.sub.1 -C.sub.12), --COOphenyl, ##STR3## --CON (phenyl).sub.2, --COalkyl(C.sub.1 -C.sub.12), --COphenyl, --Oalkyl(C.sub.1 -C.sub.12) , --Ophenyl or the radical ##STR4## in which R.sup.1 -R.sup.4 are as defined above, by reacting an aryldiazonium salt of the formula (2) ##STR5## in which R.sup.1 -R.sup.4 are as defined and Z is the equivalent of an anion of an acid having a pK.sub.a of less than 7, with an olefin of the formula (3)HX (3)
Abstract:
The displacement of halogen from a 1,2,3-trihalo-4,6-dinitroresorcinol can be carried out in an aqueous medium using alkali metal hydroxide to form 2-halo-4,6-dinitroresorcinol. The product is a useful intermediate in the synthesis of 4,6-diaminoresorcinol, which is a monomer for polybenzoxazole polymers. The process from part of a useful aqueous process for synthesizing 4,6-diaminoresorcinol.
Abstract:
A preparation process of a bis(3-nitrophenoxy) compound represented by the formula: ##STR1## wherein X is a direct bond, divalent hydrocarbon having from 1 to 10 carbon atoms or a divalent group selected from --C(CF.sub.3).sub.2, --CO--, --S--, --SO--, SO.sub.2 --or --O--, which comprises reacting 4,4'-bisphenol with m-dinitrobenzene in the presence of an alkali metal carbonate or alkali metal hydrogen carbonate having a particle size of 250 .mu.m or less while removing generated water from the reaction system during the reaction. In one embodiment of the process, the reaction is carried out while simultaneously adding 4,4'-bisphenol and m-dinitrobenzene to a reaction vessel which was previously charged with the base and an aprotic polar solvent.
Abstract:
The invention is an improved process for the large scale production of acetic acid, (dimethoxyphosphinyl) [[1,1-dimethylethyl)dimethylsilyl]oxy]-, (4-nitrophenyl)methyl ester.
Abstract:
There are provided 4-Hydroxy-2'-nitrobutyrophenone and tetrahydro-2-(o-nitrophenyl)-2-furanol and mixtures thereof, important intermediates in the preparation of the crop-selective herbicidal agent 1-{[o-(cyclopropylcarbonyl)phenyl]sulfamoyl}-3-(4,6-dimethoxy-2-pyrimidinyl)urea. Also provided is a method for the preparation of 4-halo-2'-nitrobutyrophenone, useful as an intermediate in the preparation of 1-{[o-(cyclopropylcarbonyl)phenyl]sulfamoyl}-3-(4,6-dimethoxy-2-pyrimidinyl)urea.
Abstract:
A region-specific monofunctionalization of a phenolic hydroxy onto a polyphenol for the preparation of a compound of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, alkyl of 1 to 8 carbon atoms, alkenyl and alkynyl of 2 to 8 carbon atoms, --CN, formyl, carboxy, alkoxy carbonyl of up to 9 carbon atoms, aralkoxy carbonyl or up to 12 carbon atoms and halogen and R' is a hydroxy protective group comprising reacting a polyphenol of the formula ##STR2## wherein R has the above definition with a base to form the corresponding dianion, reacting the latter with a trialkyl borate of the formulaB(OAlk).sub.3wherein Alk is alkyl of 1 to 6 carbon atoms to form a compound of the formula ##STR3## reacting the latter with a reagent capable of introducing a hydroxy protective group and reacting the latter with a hydrolysis agent for the oxygen-boron bond to obtain the corresponding compound of Formula I.