摘要:
5-Acylamino-1,2,4-triazole-3-sulfonamides, which are useful intermediates for the preparation of 1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamide herbicides are prepared from 5-amino-3-mercapto-1,2,4-triazole by sequential acylation to 5-acylamino-3-mercapto-1,2,4-triazoles, chlorination to 5-acylamino-3-chlorosulfonyl-1,2,4-triazoles, and condensation with substituted anilines to 5-acylamino-1,2,4-triazole-3-sulfonamides. 5-Acylamino-3-chlorosulfonyl-1,2,4-triazole compounds are key intermediates in the process.
摘要:
A 2,3-dihalopropanol is made by reacting 2,3-dihalopropanal with a hydrogenating agent in the presence of a transition metal-containing catalyst, under conditions such that 2,3-dihalopropanol is formed. The reaction is particularly useful as Step (3) in a process to make epihalohydrin by: (1) reacting a 3-carbon hydrocarbon with an oxidizing agent to form acrolein; (2) reacting acrolein with a molecular halogen to form 2,3-dihalopropanal; (3) reducing 2,3-dihalopropanal to form 2,3-dihalopropanol; and (4) cyclizing 2,3-dihalopropanol to make epihalohydrin. The process produces epihalohydrin using only about one mole of halogen per mole of epihalohydrin. It also uses substantially less water than existing processes.
摘要:
A process for preparing a substituted or unsubstituted 3- or 4-hydroxyalkylbenzocyclobutene compound comprises reducing a corresponding 3- or 4-formyl or ketobenzocyclobutene compound with a hydride at a temperature below that at which dimerization or oligomerization of the formyl- or ketobenzocycloutene compound or the thus-produced hydroxyalkylbenzocyclobutene compound is a significant side reaction, for a time sufficient to convert the formyl- or ketobenzocyclobutene compound to the hydroxyalkylbenzocyclobutene compound. In a two-step process, formylbenzocyclobutenes are prepared from bromobenzocyclobutenes in 90% yield or from benzocyclobutenes in a 70% yield, and then converted to hydroxymethylbenzocyclobutenes for an overall yield of about 85% from a bromobenzocyclobutene or of about 65% from a benzocyclobutene. In a two-step process, ketobenzocyclobutenes from bromobenzocyclobutene Grignard reagents and an N-alkanoyl- or N-aroyl-2-methylaziridine are converted to hydroxyalkylbenzocyclobutenes in high yields.
摘要:
Hydroxy-functional poly(ether sulfonamides) prepared by polymerizing an N,N'-dialkyl or N,N'-diaryldisulfonamide with a diepoxide in the presence of a suitable catalyst exhibit high barrier properties. These are suitable for use in the manufacture of articles such as rigid containers and flexible films exhibiting high barrier to oxygen.
摘要:
1-Chloro-3,5-difluorobenzene is chlorinated to give 4,6-difluoro-1,2,3-trichlorobenzene which in turn is nitrated and reduced to the corresponding novel aniline, 2,6-difluoro-3,4,5-trichloroaniline. Further reduction of this aniline provides 2,6-difluoroaniline with high selectivity.
摘要:
The preparation of 3,5,6-trichloropyridin-2-ol from trichloroacetyl chloride and acrylonitrile is improved by separately conducting the individual addition, cyclization and aromatization steps. By separating the steps, water and HCl, by-products of the latter steps, can be precluded from interfering with the earlier steps. The individual process steps have also been improved.
摘要:
3,4-Difluorobenzotrifluoride is prepared by contacting a 3,4-dihalobenzotrifluoride with an effective amount of KF or CsF in a polar aprotic solvent at an elevated temperature under substantially anhydrous conditions. The product can be removed as it is formed or the reaction may be run at the autogenous pressures generated by the reaction mixture in a sealed reactor.
摘要:
5-Alkyl-1-(2-pyridinyl)-1H-1,2,4-triazol-3-ols are prepared in good yield by reacting an appropriate 1-acyl-1-(2-pyridinyl)-semicarbazide with a base in the presence of a non-nucleophilic solvent. The compounds so prepared are intermediates used in the preparation of insecticides. The starting semicarbazide materials are novel compounds.
摘要:
Benzotrihalides are prepared by pyrolyzing a substituted phenyl trihaloacetate of the formula ##STR1## wherein each X is halo, nitro, alkyloxy, aryloxy, aralkyoxy, cyano, lower alkyl, haloalkyl, haloalkyloxy, alkenyl, haloalkenyl, carbamoyl, N,N-dialkylcarbamoyl, N,N-diarylcarbamoyl, or N,N-diaralkyloxy;Y is halo; andn is an integer of from 1 to 5. As an example, 4-chlorophenyl trichloroacetate is pyrolyzed at 550.degree. C. to 4-chlorobenzotrichloride.