摘要:
2(6)-(Trichloromethyl)pyridines are reduced to the corresponding 2(6)-(dichloromethyl)pyridines by treatment with a strong base and an anionic reductant derived from a reductant source material selected from the group consisting of chloroform, dimethylsulfoxide, dimethylsulfone, and a ketone having a base-abstractable hydrogen, said treatment taking place in the presence of a polar, non-hydroxylic solvent and/or a phase transfer catalyst.
摘要:
2- and 4-(Dichloromethyl)pyridines containing electron withdrawing substituents on the ring are prepared by the reaction of the corresponding 2- or 4-halopyridines with excess chloroform in the presence of a strong base in a medium containing a dipolar aprotic solvent or a phase transfer catalyst. 3-Chloro-5-(trifluoromethyl)-2-(dichloromethyl)pyridine, for example, is prepared by the reaction of 2,3-dichloro-5-(trifluoromethyl)pyridine with chloroform in the presence of sodium hydroxide and N-methylpyrrolidone. Substituted 2-(dichloromethyl)pyridines are useful as agricultural pesticides and as intermediates for the preparation of agricultural pesticides.
摘要:
2-Hydrocarbyl-3,6-dichloropyridines are prepared from dichloromethyl hydrocarbyl ketones and acrylonitrile in a two-step process involving an addition reaction under basic conditions to form intermediate 1,1-dichloro-3-cyanopropyl hydrocarbyl ketones and a subsequent cyclization reaction in the presence of hydrogen chloride. Thus, 3,6-dichloro-2-methylpyridine is prepared from 1,1-dichloro-2-propanone and acrylonitrile by the formation and further reaction of 4,4-dichloro-5-oxo-hexanenitrile. The intermediates and products are novel compounds useful in the preparation of herbicides and nitrification inhibitors.
摘要:
Novel methods for preparing 2-cyano-6-chloropyridines are disclosed. The compounds are useful as intermediates in preparing other intermediates or as intermediates directly used in making pesticides, especially herbicides.
摘要:
2-Chlorosulfonyl-5-alkoxy[1,2,4]triazolo-[1,5-c]pyrimidine compounds, such as 2-chlorosulfonyl-5-ethoxy-7-fluoro[1,2,4]triazolo[1,5-c]pyrimidine, that are useful for the preparation of 5-alkoxy[1,2,4]triazolo [1,5-c]pyrimidine-2-sulfonamide herbicides, were prepared in an improved manner from 5-alkoxy[1,2,4]triazolo [1,5-c]pyrimidine-2(3H)-thione compounds, such as 5-ethoxy-7-fluoro[1,2,4]triazolo[1,5-c]pyrimidine-2(3H)-thione, by oxidation with hydrogen peroxide to obtain novel 2,2'-dithiobis(5-alkoxy[1,2,4]triazolo[1,5-c]pyrimidine) compounds, such as 2,2'-dithiobis (5-ethoxy-7-fluoro[1,2,4]triazolo[1,5-c]pyrimidine), and subsequent chloroxidation of these intermediate compounds.
摘要:
A method for destroying chloropicrin in an aqueous medium contaminated with chloropicrin which comprises contacting the aqueous medium with a sufficient amount of an alkali metal sulfite for a sufficient period of time to convert the chloropicrin to an alkali metal chloride and to nitromethane disulfonic acid or a salt thereof, whereby the aqueous medium is rendered substantially free of chloropicrin.
摘要:
Novel linear, branched and cyclic polymers of the repeating unit ##STR1## wherein R is ethylene or propylene bearing from zero to six methyl groups and m and n are lower integers and a process for utilizing said polymers to extract salts from solution are disclosed. For example, a monomer of the formula ##STR2## is contacted with traces of water in the presence of BF.sub.3.etherate to give a homopolymer consisting essentially of repeating units of the formula ##STR3## which extracts sodium salts from aqueous solution in a thermally reversible manner.
摘要:
Elastomers are prepared from a mixture comprising a 1600 equivalent weight polyether polyol such as a glycerine initiated polyoxypropylene glycol end-capped with ethylene oxide, a diol such as diethylene glycol, a liquid polyepoxide such as the diglycidyl ether of bisphenol A and a catalyst mixture containing a quaternary ammonium or phosphonium salt and an organometal salt of the metal tin or lead such as tetrabutyl ammonium bromide and lead octoate.
摘要:
Anthranilic acids substituted in the 3- and/or 5-position are valuable intermediates for the production of agricultural chemicals. These substituted anthranilic acids can be obtained in good yield without undesirable isomeric byproducts by the oxidative ring-opening of dihydroquinolin-4-ones or quinolin-2,4-diones with t-butyl hydroperoxide in the presence of a base.
摘要:
5-Methyl-N-(aryl)-1,2,4-triazolo[1,5-a]-pyrimidine-2-sulfonamides are prepared by the cyclization of N -(3-(((aryl)amino)sulfonyl)-1H-1,2,4-triazol-5-yl)amines with 4-methoxy-3-butene-2-one or its synthetic equivalents in the presence of an aqueous base. By controlling the pH of the condensation between 8.5 and 10.5, by-product formation can be substantially reduced.