Methyl dithiocarbamates

The reaction of methyl dithiocarbamates with [Au(QF5)(tht)] leads to the formation of the neutral complexes [Au(C6F5)SC(SMe)NHR] [61], R = p-MeC6H4, o-MeC6H4, p-MeOC6H4 or 3,5-Me2C6H3. The H NMR shows that the dithiocarba-mate is S-coordinated and the IR spectra shows the absorption of the Vjnh)-... 

Bardaji, M Laguna, A., Laguna, M. and Merchan, F. (1994) Methyl dithiocarbamate gold(l) and gold(lll) complexes. Synthesis and reactivity with amines. Inorganica Chimica Acta, 215 (1-2), 215-218. 

Further, N-methyl dithiocarbamate (MDTC) (.9) and N-metylglycine (sarcosine) (10) were similarly incorporated into PVC matrices resulting in the derivatives usable to chelate forming and introduction of thiol-function as shown in following scheme. Of the two main purpose of modification of commercial polymers 1) improvement of original property of each polymer and 2) incorporation of new function into the polymeric materials, our studies would be served from the viewpoint of the latter as the fundamental design for PVC and PECH with specific functions. 

Isomerization of this cyclic disulfide (see above) affords the 1,2,4-thiadiazolidine (159), also obtainable directly from sodium methyl dithiocarbamate by conveying the wet, finely powdered salt under oxidative conditions through a pneumatic dryer.166 The production of alkyl (and phenyl) homologs by this procedure is claimed in the patent literature,166 but no physical constants are given. It is recalled that the isomerization 158->159 had previously been thought to be confined to the methyl homologs.160,164... 

The valuable intermediate 5-bromo-2-trifluoromethylaminopyridine 69 was prepared in one step from pyridyl methyl dithiocarbamate 68 by reaction with tetrabutylammonium dihydrogentrifluoride (TBAH2F3) and DBH in boiling dichloromethane (Equation 19) <1995TL563>. 

N-Bis(methylthio)methylene derivatives of amines (iminodithiocarbonates) were first introduced by Hoppe and Beckmann468 for the synthesis of a-amino acids from glycine. The A bis(methylthio)methyleneamines are prepared by reaction of a primary amine with carbon disulfide (HAZARD) in the presence of triethylamine and iodomethane to form a methyl dithiocarbamate derivative, which is then S-alkylated with a second equivalent of iodomethane in the presence of potassium carbonate as the base. Scheme 8,233 illustrates an alternative one pot procedure applied to the synthesis of /erf-butyl N-[bis(methylthio)-methylene]glycinate and its use in diastereoselective conjugate addition under... 

In a similar way, the reaction of xanthates under radical conditions leads to products and selectivities that are totally different from those in thermal rearrangements. The radical transformation usually furnishes unsubstituted hydrocarbons as reaction products. The major accomplishment of the reaction is the deoxygenation of secondary alcohols to furnish the corresponding hydrocarbons when tributylstannane is used with 0-cycloalkyl thiobenzoates or S-methyl dithiocarbamates [13]. However, the rearranged product may be observed as a byproduct [14,15]. 

A large-scale synthesis of the unsubstituted thiazole has been described starting from chloro-acetaldehyde and methyl dithiocarbamate <85S948>. Condensation of the two reagents affords 2-methylthiothiazole (272) which upon treatment with lithium in liquid ammonia and protonation with ammonium chloride yields thiazole (Scheme 69). 

The interaction of ammonia with carbon disulfide produces ammonium dithiocarbamate in solution, which reacts with 2-halo-ketones to produce thiazole-2-thiones similarly, methyl dithiocarbamate serves as a component for the construction of 2-methylthiothiazole, reducable to thiazole itself by hydrogenolysis, thus providing a good route to the unsubstituted heterocycle. °... 

Conjugated ketene thioacetals have been successfully prepared starting with aldehyde dimethylhydra-zones. In these reactions, the first-formed azaallyllithium reagent was allowed to react with carbon disulfide to form an intermediate lithium 3-dimethylhydrazonoalkanedithiolate. A second deprotonation of this dithiolate with a second equivalent of LDA then generated a dianion that was successfully alkylated with two equivalents of methyl iodide to yield the ketene thioacetal (e.g. 55 equation 25). This two step sequence avoided competing formation of a methyl dithiocarbamate by addition of LDA to carbon disulfide. 

As the MIC in Table 32 prove, Dazomet has an extraordinary broad spectrum of high activity which covers bacteria including formaldehyde resistant bacteria , fungi and yeasts, indicating that the substance is a very special formaldehyde releasing compound. One finds an explanation by looking at the pattern of synthesis which is reversible that means an intermediate of neutral to alkaline hydrolysis is iV-methyl-dithiocarbamate (see Section 9.9), a known antifungal slimicide. A pH between 4 and 9 is the optimum for Dazomet. 

According to its chemical composition the formulation exhibits antibacterial and antifungal activity. Concentrations of 2-10 mg/litre are used for slime control in pulp and paper mill systems. Pulp that may be held in storage for 8 h to 1 week may be protected by the addition of 0 01-0 03% of the 40% a.i. solution. The hydroxy-methylated dithiocarbamate may also be used as a preservative for papermaking chemicals, such as glues, starch and clay slurries and coating formulations. 

Of minor importance as microbicides for the treatment of cooling waters are dithiocarbamates such as sodium dimethyl dithiocarbamate (III.9.10.1) and potassium A -methyl dithiocarbamate (III.9.9). They function best in environments of pH 7 and higher. 

Methyl dithiocarbamates attack the reactive methylene groups of cyano-acetamide, cyanoacetic ester, or bis(phenylsulphonyl)methane with loss of methanethiol and formation of the thioamides R R CHC(S)NR R . Diazomethane and phenyldiazomethane, which is more reactive, insert into dialkyl-aminomethyl esters of dialkyldithiocarbamic acids (152 X = NR R ) or ethyl xanthic acid (152 X = OEt), giving esters (153 R = H or Ph, X = NR R or OEt) that have an extended alkylene chain. ... 

One of the authors found that N-methyl dithiocarbamate group had the excellent protection action to poly(vinyl chloride) against y-irradiation from the view point of small amount of gaseous products evolved.1 Therefore, the authors thought that this group might have the protection action against y-irradiation to poly(a-amino acid) by the same manner as that of poly(vinyl chloride). 

Reaction of PMLG-CE with Sodium N-Methyl Dithiocarbamate... 

Table I. Synthesis of PMLG Containing N-Methyl Dithiocarbamate group...

This suggests that the chlorine of the chloroethyl group was substituted to dithiocarbamate group. In this reaction for 5 hrs at 60 C, the polymer in the reaction mixture did not show the gel-like substance. At this stage it is uncertain that the intramolecular hetrocyclic intermediate may partially be formed by the neighboring group participation of the N-methyl dithiocarbamate group. 

We conclude that by 10 mole-% of the N-methyl dithiocarbamate substitution, the modified poly(y-methyl-L-glutamate) membrane is better both in antiradiation property and the oxygen permeation. 

Fumigants of various structures also are employed to preserve harvested crops, corn, small grains, and so on, from insects and other pests. Vapam, the sodium salt of iV-methyl dithiocarbamic acid, decomposes or metabolizes in the soil to methyl isothiocyanate and provides a local fumigation of fungi, nematodes, and certain insects. 

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