Benzyl dithiocarbamates

Other sulfur compounds. Several dithiocarbamates con-taining disulfide functions were non-protective in mice, as well as the S-benzyl dithiocarbamate of ethylenediamine. The S-trlthiocarbonate N-dithlocarbajnate of cysteine. III, however,... 

Since the experiment is no longer reliant on the dithiocarbamyl radical to both initiate and terminate chains (c/ Section 9,3.2.1), lower reaction temperatures may be used (where the dithiocarbamyl radical is slower or unable to add monomer) and better control over the polymerization process can be obtained. The transfer constants for the benzyl dithiocarbamates in polymerization of acrylic and styrcnic... 

Substitution of an ester of dithiocarbamic acid such as alkyl or benzyl ester (171), or their salts leads directly to 2-substituted mercaptothiazoles (172) (Scheme 87) (272, 461). Some of these compounds have an antifungal activity (561). 

AuCl3(tht) [129], AuX3[S(benzyl)2)2] (X = Cl, Br) [130] and AuC13 (thian-threne). Various dithiocarbamates and dithiolene complexes have been made, some by oxidation of gold(I) complexes (Figure 4.26). 

Certain, Y, Y-dialkyl dithioearbamates [e,g. benzyl A)/V-diethyl dithiocarbamate (14)] and xanthates have been used as photoinitiators. Photodissociation of the C-S bond of these compounds yields a reactive alkyl radical (to initiate polymerization) and a less reactive sulfur-centered radical (to undergo primary-radical termination) as shown in Scheme 9.9.30 41 4 ... 

The processes described in this section should be contrasted with RAFT polymerization (Section 9.5.3), which can involve the use of similar thioearbonylthio compounds. A. A -dialkyl dithiocarbamates have very low transfer constants in polymerizations of S and (mctb)acrylatcs and arc not effective in RAFT polymerization of these monomers. However, /V,A -dialkyl dithiocarbamates have been successfully used in RAFT polymerization of VAc. Certain O-alkyl xanthates have been successfully used to control RAFT polymerizations of VAc, acrylates and S. The failure of the earlier experiments using these reagents and monomers to provide narrow molecular weight distributions by a RAFT mechanism can he attributed to the use of non-ideal reaction conditions and reagent choice. A two part photo-initiator system comprising a mixture of a benzyl dithiocarhamate and a dithiuram disulfide has also been described and provides better control (narrower molecular weight distributions).43... 

Sequential treatment of tertiary amines containing N-methyl or /V-benzyl groups with carbon disulphide and alkyl halides gives alkyl dithiocarbamates in good to excellent yields. Thus IV-methylmorpholine, carbon disulphide and methyl iodide in THF gave 91% of compound 306366. 

In a series of papers, Matsuda et al. [291-295] employed RAFT-SIP with immobilized benzyl N,N-diethyldithiocarbamate to form polymer brushes from styrene, methacrylamides, acrylamides and acrylates, NIPAM and N-vinyl-2-pyrrolidone on various surfaces. The SIP is initiated by UV irradiation of the surface-bonded dithiocarbamates. Thermoresponsive polymer brushes were prepared by the polymerization of NIPAM and investigated by XPS, wetting experiments and mainly SPM [294]. Patterned polymer brush layers were also prepared. When chloro-methyl styrene was used as a comonomer, RAFT-SIP resulted in branching. By control of the branching, spatio-resolved hyperbranching of a controllable stem/ branch design was realized (Fig. 9.32) [293, 295]. 

N,N-Dialkylthlo- and dithiocarbamate herbicides include several -alkyl and -benzyl compounds without mutagenic activity and three -chloroallyl derivatives which are promutagens,... 

Examples of surface functional derivatization by iniferter-based crossrecombination are shown below. A dithiocarbamated benzyl polymer surface was used as a model surface. When n-propyl N,N-diethyldithiocarbamate was used, XPS measurements showed that the complete loss of both N and S atoms but a marked increase in the C content of the surface was noticed. 

The Inifer technique enables us to fulfil some requirements of polymer architecture even in some radical processes. An amplified form may be applied, the Iniferter variant, where the radical initiator simultaneously acts as a transfer and terminating agent. Otsu et al. used sulphides and disulphides (tetraethylthiuram disulphide, PhSSPh, Ph2S, PhCH2SSCH2Ph) [96] and carbamates (benzyl-A,A-diethyldithiocarbamate, p-xylylene-A,7V-diethyl-dithiocarbamate) [97] in the photopolymerization of methyl methacrylate and styrene, and phenylazotriphenylmethane in the polymerization of methyl methacrylate [98]. Living radical polymerizations yield polymers with defined end groups or the required block copolymers. 

At 20 °C 4-amino-5-aminomethyl-3-benzyl-l,2,3-triazole (408) gives with CS2 the dithiocarbamate (409), which upon heating affords the novel heterocyclic system 1,2,3-triazolo[4,5-d][l,3]thiazine (410) (and not the expected 8-azapurine) <8oag319, 80aG(E)310,... 

Di-block copolymers may also be formed by using dithiocarbamate free radicals. Indeed, copoljoners containing poly(styrene) and poly(hydroxyethyl methacrylate) blocks have been obtained by a two-step procedure [145]. Firstly, styrene is photopolymerized in the presence of benzyl A,A-diethyldithiocarbamate (BDC) by a living radical mechanism [146]. In fact, as the benzyl and thiyl radicals, formed by the photoliagmentation of BDC, participate mainly in the initiation and termination reactions respectively, polystyrene with a dithiocarbamate end group is thus obtained. The successive UV irradiation of this polymer, in the presence of hydroxyethyl methacrylate (HEMA), gives rise to the di-block copolymer, according to Scheme 42. 

The reaction of carbon disulfide with o-amino benzyl amines (X) is analogous to that with I.J-diamines. In the former 1,2,3,4-tetrahydro-quinazoline-2-thiones (XI) are formed 56, 59, 60, 269). Cyclization of the intermediate dithiocarbamic acids here is generally done by refluxing with alkali. These compounds are reviewed in Table 3. 

Miscellaneous Systems Many systems have been mentioned [li,m,2i] acyloxy and acylsilyl phosphine oxides, phosphine sulfides, cyclic compounds, benzoyloxa-ziridine derivatives, dibenzoylmethane derivatives, triazene and pentaazadiene moiety containing compounds. New developments include benzyl benzoin benzyl ethers [112], dithiocarbamates [113], ketoamides [114], phosphonates [115], bromo-acetylpyrene [116], alkylimides [117], aryloxy naphthalene [118], oligosilanes [119], bisphosphine sulfides [120], sulfamic esters of benzoin ethers [121], sulfur [122], or carbohydrate [123] containing compounds. 

Certain yY V-dialkyl dithiocarbamates e.g. benzyl A At-diethyl dilhiocarbamate... 

A reagent consisting of NIS and 70% HF-pyridine converts xanthates R-OCS2Me (R=alkyl) to R-OCF3 (R=primary) or R-F (R = benzylic, secondary, tertiary) by an oxidative desulfurization-lluorination reaction. The C-S bonds of the dithiocarbamates are directly replaced by C-F bonds using NIS and tetrabutylammonium dihydrogentrifluoride (TBAH2F3) (eq 14). ... 

Metallic complexes based on Ni, Co, and substituted phenols, thiophenols, dithiocarbamates, or phosphates are used. Typical representatives are nickel-di-butyldithiocarbamate, n-butylamin-nickel-2,2 -thio-bis-(4-terf-octyl-phenolate), nickel-bis-[2,2 -thio-bis-(4-rcri-octyl-phenolate)] and nickel-(0-ethyl-3,5-di-terf-butyl-4-hydroxy-benzyl)-phosphonate. But their use is not as widespread as for other UV absorbers because they tend to be green. 

C. Schilli, M. LanzendOrfer and A. H. E. Muller, Benzyl and Cumyl Dithiocarbamates as Chain Transfer Agents in the RAFT Polymerization of N-lsopropylacrylamide. In-Situ FT-NIR and MALDI-TOF MS Investigation, Macromolecules (submitted). 

Benzyl Zlmat. See Zinc dibenzyl dithiocarbamate Benzytol. See Chloroxylenol Berberine chloride... 

A soln. of GS2 in abs. ether added dropwise with stirring and ice-salt cooling to a soln. of 2 moles benzylamine in the same solvent, the precipitated benzyl-ammonium dithiocarbamate removed by filtration, dissolved in benzene, a soln. of pyrocatechyl phosphorotrichloridate in the same solvent added dropwise with stirring and ice-cooling, then refluxed 1 hr. on a water bath benzyl isothiocyanate. Y 84%. F. e., also by POGI3 instead of pyrocatechyl phosphorotrichloridate with somewhat lower yields, s. D. Martin, E. Beyer, and H. Gross, B. 98, 2425 (1965). 

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