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United States Patent Office Patented Nov 3,285,929 United States Patent Office Patented Nov. 15, 1966 1. 2 3,285,929 and R represents an organic radical or a hydrogen radi FUNGCDAL COMPOUNDS CONTAINING cal. THE NSCFC-GROUPS Suitable imide compounds of the indicated type are Erich Kauke, Cologne-Fliétard, Engelbert Kuhle and illustrated by Formula II: Ferdinand Grewe, Cologne-Stammheim, and Helmut Kaspers and Richard Wegler, Leverkusen, Germany, (II) X assignors to Farbenfabriken Bayer Aktiengesellschaft, R^ Yscrol, Leverkusen, Germany, a corporation of Germany No Drawing. Filed Oct. 31, 1961, Ser. No. 148,845 Y Claims priority, application Germany, Nov. 3, 1960, in which R represents one or more organic residues and F 32,468; Nov. 25, 1960, F 32,620 0. X is part of an acyl group, such as for example 8 Claims. (C. 260-301) O O The present invention relates to new and useful im provements in fungicidal preparations and more particu -- and -C- larly to improved fungicides. This invention also relates O to methods of protecting organic material subject to at 15 The organic residue may be aliphatic, aromatic, ali tack by low orders of organisms. This invention further cyclic, heterocyclic, and their substituted derivatives, and relates to the synthesis of new chemical compounds, may be attached furthermore to the above said group namely N-thiomonofluoro-dichloromethyl imides of the also by heteroatoms such as nitrogen, sulfur or oxygen. following general formula The novel compounds of this invention may be pre 20 pared in general by the reaction of dichloro-monofluoro methyl-sulf-enylchloride (CISCFC), with the corre sponding imide or the metal salt of this compound. Formula III generally illustrates this reaction where M in which X stands for organic acyl radicals and Y stands 25 represents hydrogen or a metal, and where both of the for another acyl radical or another suitable organic acyl groups are derived from carboxylic acid groups: radical; X and Y may be linked together, too, to form a (III) common ring system. O O Similar compounds of the aforementioned type which -C -C contain instead of an =NSCFCl-group the =NSCCl3 30 N N group are known already from the literature. U.S. N-M -- CSCF Cli --> N-s-CFC; -- MCl al-O -C Patents 2,553,770; 2,553,771; 2,553,772; 2,553,773; | 2,553,774; 2,553,775; 2,553,776; 2,844,628, for instance, O O describe a large number of such compounds containing This reaction is shown only to illustrate this inven a trichloro-methylmercapto group. 35 tion and not intended to limit it in any way. Other in In accordance with the present invention it has now ventive compounds as it may be seen from the examples been found that a large number of organic compounds can be prepared by exactly the same method. containing the =NSCFCl-group are extremely effective The reaction to prepare the inventive compounds may for controlling the growth of fungi, and in this respect be carried out at room temperature or at slightly elevated are superior to those compounds of the prior art con 40 temperature either in an aqueous medium or also in inert taining the =NSCCl3-group. organic solvents such as benzene, dioxane, carbon tetra The physiologically active compounds of this invention chloride and the like. If the free imides are used, i.e. if may thus best be represented as having the = -NSCFCla M stands for hydrogen, the reaction is carried out with group in which the nitrogen is linked to two carbon preferably in the presence of acid-binding agents, such as atoms, two acyl groups, or one acyl group and one car 45 alkali metal hydroxides, -carbonates, -alcoholates, and bon atom. The phase acyl group refers especially to the like, or also in the presence of tertiary organic amines. groups of the following character Starting materials for the inventive reaction broadly may be seen from the patent specifications mentioned at the beginning. As some examples of the specifications 50 there may be mentioned: phthalimide, tetrahydrophthali mide, 3.6-endomethylene-A-tetrahydrophthalimide, 3-ni etc. (see Hackh, "Chemical Dictionary,” second edition, trophthalimide, succinic imide, 2.4-dioxothiazolidine, par page 21). When the nitrogen atom of the =-NSCFCl2 abanic acid, 1.4-dioxyphthalazine, benzene sulfonic acid group is linked to one acyl group, the compounds may methylamide, 4-chlorobenzene-sulfonic acid anilide, chlo be regarded as amide derivatives. When both of the free 55 romethane Sulfonic acid anilide or N,N,N'-trimethylsulf linkages of the =NSCFCl-group are taken up by acyl amide. groups, the compounds may be regarded as imides (see Another method suitable for the preparation of the in Sidgwick's “Organic Chemistry of Nitrogen" 1937 edi ventive compounds consists in reacting the thio-trichloro tion, pages 136 and 152). methylamides known from the aforementioned specifica Suitable amide compounds of the indicated type are 60 tions, with anhydrous hydrogen fluoride. Most surpris thus illustrated in Formula I: ingly under even severe reaction conditions only one chlo (I) R-X-NSCF Cl rine atom is split off and replaced by fluorine. The fol k lowing reaction scheme may illustrate this method: 65 HF . in which R represents an organic residue, possibly linked =NSCCls - =NSCF Cls -- Hol to X via nitrogen, oxygen or sulfur, too, X is part of an The two bonds before the nitrogen atom may preferably acyl group, such as for example stand for the radical mentioned in the foregoing descrip tion. 2 2 70 Anhydrous hydrogen fluoride in the meaning of the -i- and -C- above said statement should be a commercial product with O a content of about 2% of water, but preferably not more. 3,285,929 3. 4. The reaction usually is carried out under commercial Example 2 pressure and at temperatures between 0 and 20° C.; pref 20 grams of N.N.dimethyl-N'-phenylsulfamide and 17 erably anhydrous hydrogen fluoride is used in an excess grams of dichlorofluoro-methane sulfenic chloride are so that it serves at the same time as a diluent does. The dissolved in 100 ml. of toluene and treated with 11 grams excess easily can be removed then by distillation. Of of triethylamine at room temperature. Thereby the tem course, also other inert solvents may be used as diluents. perature rises to about 40° C. After stirring for some These inert solvents preferably are nitrobenzene, diethyl time water is added, the toluene layer is dried over sodium ether, dioxane and the like. sulfate and concentrated in vacuum. The crystalline The new inventive compounds as stated above are valu residue melts after recrystallization from alcohol at 110 able pesticides with especially fungicidal action and should O 112 C. There are obtained 18 grams of the N.N- be used in the field of plant protection. The main advan dimethyl- N' - phenyl- N' - dichlorofluoromethyl - thio tage of the inventive compounds over the trichloro com sulfamide. pounds of the prior art is their better tolerableness on In analogous manner there may be obtained the com plants especially regarding phytotoxicity, without de pounds of the following formulae: crease in fungicidal activity. A further advantage over 5 the prior art compounds is a longer lasting activity and better stability. From the following experiment there is to be seen the high initial activity of the inventive compounds. The test is a green-house experiment and has been carried out 20 with tomato plants (Bonny best). Aqueous emulsions of the compounds shown in the table below have been sprayed on the plants. The aqueous emulsions have been M.P. 81-82° C. prepared by admixing the active ingredient with the same (CH3)2N-SO-N-SCF Cl amount of dimethyl formamide and a commercial non 25 ionic emulsifier (NP10). Plants sprayed with these solu tions are inoculated after 24 hours with Zoosporangia of Phytophthora infestans, and placed in humidity chambers Phytophthora infestans, and placed in humidity chambers 30 OCH at a temperature of 20° C. and a relative humidity of 100%. They are kept there for 5 days. After that the M.P. 97° C. infestation has been checked and is shown in the table (HC):N-SO-N-SCF Cl below in comparison to an untreated control test, infesta tion of which is set as 100. -CH 35 IDegree of infestation at a conc. of active ingredient O in percent (aqueous emul M.P. 60-61. C. sion) (H3C):N-SO-N-SCF Cl 40 0.025 0.0062 Cl CO O NSCF Cl O 5 M.P. 82° C. (HC),N-SO-N-SCF Cl CO HC N Nson-scFC), O 3 50 3C CETs OCl CO M.P. 116° C. NSCCl3 3 14 Example 3 N 55 38 grams of A-tetrahydrophthalimide together with CO 10 grams of caustic soda are dissolved in 170 ml. of water HC and treated with 43 grams of dichlorofluoromethane N sulfenic acid chloride at a temperature of 13-15 C. Ns onsc Cla l 13 The crystal mass obtained is after stirring for some time C CEs 60 filtered off with suction and washed with water. The Control----------------------------------- 100 N-dichlorofluoromethyl-thio-tetrahydrophthalimide melts at 102-104 C. In analogous manner there are obtained the com Example 1 pounds of the following formulae: 18.5 grams of the potassium salt of phthalimide are 65 CO dissolved in 100 ml. of toluene and treated with a solu tion of 17.0 grams of dichlorofluoromethane sulfenic acid NSCF Cl chloride in 50 ml. of toluene at room temperature. There by the temperature rises to about 40° C. Heating is con CO tinued for about half an hour at 80° C., the reaction 70 M.P.
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