1,3-Diphenyl-2-thiourea

Figure 11.4 shows the relationship between efficiency and concentration of some thiourea derivatives and gelatin in the pickling of cold-reduced and annealed strip in 6% w/w sulphuric acid at 85°C. The thiourea derivatives, diluted with sodium chloride, gelatin and a wetting agent, are used commercially. Mono- and di-o-tolyl thioureas are stable in this pickle for at least 50 h, but diphenyl thiourea and gelatin decompose after four or five hours. 

Various thiourea ligands have been used in the synthesis of mixed ligand complexes. A series of complexes [NiQ2L2] (HQ = ethylacetoacetate, L = thiourea, allyl-, benzoyl-, methyl-, diphenyl-thiourea) have been prepared. The complexes are all paramagnetic (/i = 3.02-3.27/iB) and have been assigned tra 5-octahedral structures.1014... 

The conversion of symmetrical into unsymmetrical thioureas is exemplified by the formation of Af-cyclohexyl-Af -phenylthiourea when yV,iV-diphenyl thiourea is heated with cyclohexylamine and triethylamine in acetonitrile367. Carbonylation of lithium piperidide in the presence of tellurium generates the lithium carbamotellurate 307, which is trapped as the 7V-ethyl carbamotellurate 308 by ethyl bromide368. 

Pentanitro, CigH OioS, and Hexanitro, Ci3HeN0Ot2S, derivs of Diphenyl thiourea were not found in the literature thru 1966... 

Isothiocyanate sulfides, (RNCS)2S, arise similarly from isothiocyanates by successive treatment with bromine in anhydrous chloroform, and hydrogen sulfide158,160 or ethanol.161 The phenyl homolog has also been obtained by the action of thiophosgene on diphenyl-thiourea,162 or aluminum chloride on phenyl isothiocyanate.103... 

Symmetrical diphenyl thiourea (thiocarbanilide) (C HjNH CS is a solid, mp 154 0. When heated with concentrated HC1, the compound yields aniline plus phenylisocyanate. Formed by the reaction of aniline and CS2, symmetrical diethylthiourea (C2H5NH)2CS is a solid, mp 77°C. 

Centr 3 was prepd by Dains et al(Refs 1 2) by two methods a)Heating of equi-molecular quantities of N-ethyl-N,N -diphenyl-thiourea and methylphenylcarbamyl chloride at 150-160° or b)Heating a mixt of ethylaniline, methylphenylcarbamyl chloride and pyridine at 140°... 

A single mixing device connected to a stainless steel tube of about 10 m length and 0.25 mm diameter was used [25], The feasibility of performing a nearly spontaneous reaction could be shown. Further studies on the desymmetrization of thioureas showed that for the diphenyl thiourea/cydohexylamine system reasonable reaction... 

SYNS DFT N,N -DIPHENYLTHIOCARBAMIDE sym-DIPHENYLTHIOCARBAMIDE N,N -DIPHENYL-THIOUREA sim-DIPHENYLTHIOUREA 1,3-DIPHENYLTHIOUREA 1,3-DIPHENYL-2-THIOUREA... 

Manufacture, There are many ways of manufacture. In practice it is made from phenylglycine, naphthalene or diphenyl thiourea. 

Group VI Donors. The binding energies of the S 2p and N Is electrons of diphenyl-thiourea when bound to osmium(ii) have been measured. ... 

A.l.lJFormation of diphynel urea. Aniline may react with COS to yield both diphenyl urea and diphenyl thiourea in a 1 1 ratio (53)... 

In addition, diphenyl thiourea can be produced via the reaction of aliphatic amine and 82- Firstly, alkyl dithiocarbamate is prepared by the following reaction ... 

Then diphenyl thiourea forms when alkyl dithiocarbamate is neutralized by aliphatic amine ... 

Alkyl diphenyl thiourea can be produced by the following reaction ... 

Typical procedure. Diphenylcarbodiimide 1699 (R = R = Ph) [1278] Triphenylphos-phine (2.62 g, 0.01 mol) in THF (10 mL) was added dropwise to N,N -diphenyl-thiourea (2.28 g, 0.01 mol) and diethyl azodicarboxylate (1.74 g, 0.01 mol) in THF (20 mL) at room temperature. After standing overnight, the solvent was removed under reduced pressure and the residue was extracted with light petroleum (bp 30-60 °C) to separate soluble material from the remainder. The light petroleum extract was concentrated and distilled to give diphenylcarbodiimide bp 85-90 °C/ 0.2 mmHg, 1.27 g, 65%. 

As an organic accelerator, ethylene thiourea (ETU), which is preferably used in non-dusty forms, is widely used. Different derivatives of thiourea, such as diethyl thiourea (DETU) and diphenyl thiourea (DPTU), are typical ultrafast accelerators, especially suitable for continuous cure. 

Phenylimino-oxalic acid dichloride (prepared from oxalic acid, phosphorus pentachloride, and aniline in benzene) is likewise a suitable starting material in this synthesis of both thiazolidines and condensed ring-systems incorporating the thiazole system (see Chapter 14, imidazo[2,l-b]benzothia-zoles and thiazolo[3,2-a]benzimidazole). Its interaction with diphenyl-thiourea produces 3-phenyl-2,5-bis(phenylimino)thiazolidin-4-one (Scheme 6). "... 

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