Thio cresol

Bromine in dry chloroform added dropwise with stirring at room temp, during 5 hrs. to a soln. of benzylidene-p-nitraniline in the same solvent, and kept 6 hrs. at 4° dibromide (Y 71%) treated 6 hrs. at 35° with thiourea in 90%-ethanol benzylidene-p-nitraniline. Y 63%. Also bromine elimination by other nucleophiles such as iodide, thiosulfate, thiophenolate, and thiocyanate ions, or thio-cresol s. Nasir-ud-Din et al., Ghem. Ind. 1967, 1875. 

Thio-p-cresol (p-tolyl mercaptan), p-CHjCjH SH. This compound may be similarly prepared from p-toluenesulphonyl chloride (Section IV,207). The thio-p-cresol crystallises in the steam distillate and is collected and dried m.p. 43°. The b.p. under normal pressure is 194r-195°. 

Figure 6.20 Collision activation mass spectra of the El induced molecular ions m/z 358 of 2,2 -thio-bis-(4-methyl-6-t-butylphenol) (1), 4,4 -thio-bis-(6-t-butyl-o-cresol) (2) and 4,4 -thio-bis-(6-t-butyl-m-cresol) (3) (see Scheme 6.3). After Egsgaard et al. [232]. Reprinted from Trends in Analytical Chemistry, 11, H. Egsgaard et al., 164-168, Copyright (1992), with permission from Elsevier...

As to the main limitation of MS vs. FTIR detection, namely the inability to distinguish closely related isomers, this rarely plays a role in additive analysis. Notable examples of isomeric additives are the bifunctional stabilisers C22H30O2S as 4,4 -thio-bis-(6-t-butyl-m-cresol), 2,2 -thio-bis-(4-methyl-6-f-butylphenol) and 4,4 -thio-bis-(2-methyl-6-f-butylphenol) (Section 6.3.6), the bisphenolic antioxidants C23H32O2 (Plastanox 2246 and Ethanox 720) and the phenolic antioxidants C15H24O (nonylphenol and di-f-butyl-p-cresol). 

Method A The glucopyranosyl bromide (1 mmol) in CH2C12 (10 ml) and HzO (10 ml) is added to the phenol (3 mmol) and TEBA-C1 or Adogen (0.2 mmol) in aqueous KOH or NaOH (25 mmol) and the mixture is stirred at room temperature for 8-60 h. The organic phase is separated, washed with H20, dried (MgS04), and evaporated to yield the O-aryl derivative (68% from phenol 60% from 2-cresol 53% from 3-chlorophenoI, 54% from 4-methoxyphenol 56% from 4-nitrophenol 57% from 1-naphthol 44% from thio-phenol 36% from 8-hydroxyquinoline). 

Thiobis(6-t-butyl-o-cresol), 503 Thio-Claisen rearrangement, 405 Thiocyanogen, 503... 

This has been prepared by the reaction of the sodium salt of 4-methyl thio-m-cresol (52) with 0,0-dimethylthiophosphoryl chloride in acetone at 50 C [54,55]. 

A further example is the preparation of p-tolyl triphenylmethyl sulfide from triphenyl-methanol and thio-p-cresol.370... 

For instance, Zincke and Frohneberg624 obtained / -toluenesulfonyl chloride, m.p. 69°, by passing chlorine to saturation into a solution of thio-p-cresol in 5 parts of glacial acetic acid, setting the mixture aside for a short time, and then evaporating it. 

Toluenesulfonyl bromide, prepared from thio-p-cresol (3 g), glacial acetic acid (15 g), and bromine (6 g), melts at 93-94° after recrystallization from a little light petroleum. 

The yellow diamagnetic anions [CrgCCOXoSR]" (R = H, Me, Et,Ph) are formed on oxidation of aqueous Na2[Cr2(CO)io] by RSH, accompanied by the evolution of hydrogen, but when RSH is thio-p-cresol the mononuclear anion [Cr(CO)5SR] (R = CjH4Me) is isolated . The monomeric carbonyl derivatives M(CO)5SR" can be prepared by using the mercury thiolates only a small amount of the dimeric species is obtained . The... 

Straightforward UV spectroscopy is liable to be in error because of interference by other highly absorbing impurities that may be present in the sample [59-62], Interference by such impurities in direct UV spectroscopy has been overcome or minimised by selective solvent extraction or by chromatography [60], However, within prescribed limits UV spectroscopy is of use and, as an example, procedures are described next for the determination of lonol (2,6-di- e -butyl-p-cresol) and of Santonox R (4,4"-thio-bis-6-terUbutyl-m-cresol) in polyolefins [63-66],... 

Campbell and Wise [2] applied column chromatography to the determination of known phenolic antioxidants in polyethylene (PE). This method is applicable to the analysis of mixtures of Santowhite powder (4, 4"-butylidene-bis-(6- er -butyl-w-cresol) with BHT (2,6-di-ter -butyl-p-cresol) and mixtures of Santonox R (4, 4 -thio-bis-(6-fert-butyl-m-... 

Quantitative procedures are described next for determining Santonox R (4,4 -thio-bis-6- er -butyl-w-cresol), and the UV stabiliser Cyasorb UV 531 (2-hydroxy-4-w-octoxybenzophenone) in PE, in amounts down to 20 ppm in polymer with an accuracy of 20% of the determined amount. 

Tert-butyl -4-methyl-6-methylphenol)-p -cresol Phenylethylpyrocatechol and phenylisopropylpyrocatechol 2,2 -Thio -bis -(4 -methyl -6 -tert -butylphenol)... 

Spell and Eddy [3] described infrared (IR) spectroscopic procedures for the determination of up to 500 ppm of various additives in polyethylene (PE) pellets following solvent extraction of the additives at room temperature. They showed lonol (2,6-di-ter -butyl-p-cresol) and Santonox R (4,4 -thio-bis(6-ter -butyl- /-cresol)) are extracted quantitatively from PE pellets by carbon disulfide in 2-3 hours and by isooctane in 50-75 hours. The carbon disulfide extract is suitable for scanning in the IR region between 7.8 and 9.3 (xm, while the isooctane extract is suitable for scanning in the UV region between 250 and 350 nm. 

Plastics utensils Sunflower seed oil Santonox R antioxidant (4,4 thio-f /s-6-tert butyl-w-cresol) Thin-layer chromatography [149, 150]... 

Nevertheless, a preponderant proportion of cresols and xylenols is acknowledged after FCC cracking of heavy products or SC cracking of phenols. The presence of thio-phenols is seldom monitored. 

Several early workers studied the position of the SH stretching absorption band. Bell [1,2] was able to show that a number of simple mercaptans such as propyl, butyl and woamyl mercaptans gave a well-defined but rather weak absorption at 2650—2550 cm". He was also able to show that the bands near 2550 cm" in thiophenol and thio-p-cresol were absent from the corresponding sulphides. 

N,N -hexane-1,6-diylbis(3-(3,5-di-tert-butyl-4-hydroxy-phenylpropionamide)) 3,3 ,3 ,5, 5 ,5 -hexa-tert-butyl-a,a ,a -(mesitylene-2,4,6-triyl)tri-p-cresol 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1 H,3H,5H)- trione Phosphite bis-(2,4-di-t-butylphenol) pentaerythritol diphosphite tris (2,4-di-tert-butylphenyl)phosphite phosphoric acid, (2,4-di-butyl-6-methylphenyl)ethylester distearyl pentaerythritol diphosphite Optical brightener 2,2 -(2,5-thio-phenediyl)bis(5-tert-butylbenzoxazole)... 

Cyclohexene in acetic acid added at 25° to a soln. of thiocyanogen chloride, prepared from Pb-thiocyanate and chlorine in acetic acid with subsequent addition of 2,6-di-fer -butyl-p-cresol as radical inhibitor rran -l-chloro-2-thio-cyanatocyclohexane. Y 77%. F. e. s. R. G. Guy and I. Pearson, Soc. Perkin I 1973, 281. 

Sterically hindered phenols, such as 2,6 di-tert-butyl-p-cresol (BHT), long chain 3-(3,5 di-tert-hutyl-4-hydroxyphenyl)-propionate or sebacate are the preferred substances for the stabilization of polystyrenes. Preferred thio compounds are long-chain thiodi-propionates. The combination of thio compounds with sterically hindered phenols leads to thioether substituted phenols. Suitable phosphorous compounds include substituted phenylphosphites, such as tris-nonylphenyl phosphite (TNPP) or phos-phonite. 

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