P Toluenethiol

A strong acceptor TCNE undergoes [2+2] rather than [4+2] cycloaddition reactions even with dienes. 1,1-Diphenylbutadiene [20] and 2,5-dimethyl-2,4-hexadiene (Scheme 5) [21] afford mainly and exclusively vinyl cyclobutane derivatives, respectively. In the reactions of 2,5-dimethyl-2,4-hexadiene (1) the observed rate constant, is greater for chloroform solvent than for a more polar solvent, acetonitrile (2) the trapping of a zwitterion intermediate by either methanol or p-toluenethiol was unsuccessful (3) radical initiators such as benzyl peroxide, or radical inhibitors like hydroquinone, have no effect on the rate (4) the entropies of activation are of... 

Solvolysis of either 178a or 178b in 80% aqueous ethanol in the presence of p-toluenethiolate or benzylthiolate gives a 1 1 mixture of cis and trans products. A 1 1 ds trans product ratio also was observed in acetic acid in the presence of either sodium acetate or silver acetate. The 1 1 product ratio was observed as early as 10% reaction and remained constant throughout the reaction. The acetolysis is accompanied by extensive ion-pair return, which causes cis trans, 178a 178b, isomerization. However, this isomerization... 

The products are (220), probably formed by the dimerization of (219), and the 2-alkoxy-l,2-thiaphosphole derivatives (218). Analogues of the latter are obtained with p-toluenethiol and dialkylamines. The compound (217 R=Ph) is more reactive than (217 R Me ) and will react with aniline on addition of triethylamine even at room temperature, from which the formation of (221) was observed by spectroscopic characterization. Even more reactive is cyclohexylamine which furnishes an analogue of (221) without addition of strong base. ... 

TABLE 14. Synthesis of vinyl sulfides (186) by the reaction of magnesium alkyUdene carbenoids with lithium p-toluenethiolate followed by some electrophiles... 

There are several examples of this approach to thiophenes. The reaction of thiophenol with acetylene in the vapor phase at 600-650 °C gave benzo[h]thiophene in 71% yield. p-Toluenethiol affords 5-methylbenzo[h ]thiophene in 54% yield under the same conditions (54HC(7)l). The best example of this type of synthesis was the reaction of 3-mercaptocy-clohexanones (235) with glyoxal to form the thiophenes (236), which was the subject of a patent (70USP3511854). The reaction proceeds smoothly under reflux conditions, using ah inert solvent, such as benzene or toluene, which will azeotrope with water, and a protic acid catalyst. A solution of (235) in the solvent is added to 40% aqueous glyoxal solution containing some acid. After reflux the thiophene (236) can be isolated in 70-90% yield. 

Reduction of l,2,4-triazin-3-ones (84) with Raney nickel, zinc and acetic acid, lithium aluminum hydride, sodium borohydride, titanium(III) chloride, p-toluenethiol, hydrogen and a palladium catalyst, or electrochemically, produces 4,5-dihydro-l,2,4-triazin-3-ones (268) (78HC(33)189, p. 246, 80JHC1237), which may be further reduced to 1,4,5,6-tetrahydro-l,2,4-triazin-3-ones (269). l,2,4-Triazin-3-ones (84) with hydriodic acid and phosphorus yielded imidazoles (05LA(339)243). 3-Alkoxy-l,2,4-triazines (126) and sodium borohydride gave the 2,5-dihydro derivatives (270) (80JOC4594). 

Truce and Kassinger (1958b) found only one product, which was assumed to be the cis isomer, from the reaction of p-tolylthiotrichloro-ethylene with p-toluenethiolate ion. It was shown later (Truce et al., 1965) that it is the trans isomer. 

The requirement for a positive j8-carbon is also reflected in Table 8, which summarizes the known Hammett p values. All these are positive, with the least reactive system showing the highest response to substituent change. The p value for the diarylhaloethylene-ethoxide ion reaction is the highest, followed by that for the reaction with the more reactive p-toluenethiolate ion. In the a-arylsulphonyl-/J-chloroethylene series, the highest values are again for the slow azide reaction, but... 

The rule of trans addition of thio nucleophiles to acetylenes (Truce and Simms, 1956 Truce et al., 1960, 1961 Truce, 1961) and other criteria had been used by Truce and coworkers in their systematic study of the substitution routes of the chloroethylenes with p-toluenethiolate ion. 

On the other hand, the electrophilicity of the /3-carbon is increased by the combined effect of the two a-chlorines, and with p-toluenethiol both the addition product (137), and the abnormal substitution product (139) are formed (Truce and Boudakian, 1956a). Formation of (139), rather than of its isomer (133), was ascribed to the tendency to decrease the steric interactions between large groups in the transition state for... 

Diastereoselective 1,4-addition of cuprates to enones. 5-Trimethylcyclohex-enone (1) has been resolved by kinetic resolution via the adduct with p-toluenethiol by cinchonidine. It undergoes highly diastereoselective addition with cuprates in the presence of ClSi(CH3)3 and HMPT to furnish only the trans-1,4-adducts in 88-95% yield. ... 

The reaction of 2-chloro-l,l-dialkyl-6-nitroacenaphthenes (8-10) with azide and p-toluenethiolate ions takes place by the S l mechanism74. This reaction gives the substitution products, despite the fact that the nitro group and the chlorine-bearing benzylic carbon are attached to different aromatic rings. 

Truce WE, Goldhamer DL (1959) The stereochemistry of the base-catalyzed addition of p-toluenethiol to sodium and ethyl phenylpropiolate. J Am Chem Soc 81 5795-5798... 

TOLUENETHIOL see TGPOOO 4-TOLUENETHIOL see TGP250 o-TOLUENETHIOL see TGPOOO p-TOLUENETHIOL see TGP250... 

A 2-amino-5-substituted-pyrazine refluxed with p-toluenethiol, 2-methoxy-ethanol, and 2-amino-6-formyl-4-hydroxypteridine followed by heating with acetic anhydride gave the 2-amino-4-hydroxy-6-[A -(5 -substituted-pyrazin-2 -yl)-acetamidomethyl]pteridine (34) (1244). 2-Amino-5-phenylpyrazine with isobutyral-dehyde in ether at room temperature gave 2-(3-isopropyl-6, 6-dimethyl-5, 6-dihydro-l, 2, 4 -trioxin-5 -yl)aniino-5-phenylpyrazine (35) (1245). 

Use of thiirane 1,1-dioxide affords a useful synthesis of ethanesulfinates with the following functions in the 2-position thiol, disulfide, trisulfide, thiosulfate, thiosulfonate, and phos-phorthioate. Reaction of episulfone (83) with sodium p-toluenethiolate gives the sulfinate (84), which can be converted to the sulfone (85) (Scheme 35). Similarly, (83) is converted to the benzyl counterpart (86), which is desired for possible debenzylation to the thiol since the salt (86) is difficult to purify, it is converted to the ethyl ester (87) <86JOC5235>. 

The m-dich loroethy lene 170 reacts with sodium p-toluenethiolate... 

Examples of acyclic vinylic systems that undergo nucleophilic substitution with complete inversion of configuration are very rare. The reaction of l,2-dibromo-l,2-difluoroethene (9) with p-toluenethiolate affords products of apparently inverted structure without loss of stereochemical purity (Scheme 8). However, the authors are not sure whether this is due to the stereospecificity of the reaction or to the thermodynamic stabilities of the products. 

Truce and collaborators (7-9) have shown that cis-dichloroethylene 20 reacts readily with sodium p-toluenethiolate in the presence of sodium ethoxide to give cis-1,2-bis-p-toly1mercapto-ethylene 22 while the trans-isomer 21, when subjected to the same conditions is recovered unchanged. Convincing evidence was obtained that the conversion M takes place via the intermediates 23, 24, and Truce and Simms (9) have also observed that the base-catalyzed addition of -toluenethiol to phenyl acetylene and to 2-butyne yields cis-styryl -tolylsulfide ( ) and 2-p-tolylmercapto-trans-2-butene (27) respectively. 

Synonyms 4-Mercaptotoluene p-Mercaptotoluene 4-Methylbenzenethiol p-Methylbenzenethiol 4-Methylphenyl mercaptan p-Methylphenyl mercaptan 4-Methylthiophenol p-Methylthiophenol 4-Thiocresol 4-Toluenethiol p-Toluenethiol 4-Tolyl mercaptan p-Tolyl mercaptan p-Tolylthiol Classification Aromatic mercaptan Empiricai CyHaS Formuia CH3C6H4SH... 

Toluenethiol. See o-Thiocresol 4-Toluenethiol. See p-Thiocresol a-Toluenethiol. See Benzyl mercaptan o-Toluenethiol. See o-Thiocresol p-Toluenethiol. See p-Thiocresol Toluene trichloride Toluene, a,a,a-trichloro. 

The degree of trans stereoselectivity for nucleophilic additions of p-toluenethiol derivatives to negatively substituted acetylenic compounds (Y=CN SOgCgH Me-p, CsH NOj-p, CO Me, CONH2, COMe) in methanol is dependent on the nature of the activating group Y, and... 

Co-oxidation of thiols with 1,3-butadiene, the simplest conjugated diolefin, has been studied in the presence of r-butylamine . Products derived from 1,2- and 1,4-addition were observed in the reaction with methane- and ethane-thiols, predominant 1,2-co-oxidation products were formed when benzene or p-toluenethiol were used (equation 104). 

Dibromoethane added dropwise to a stirred mixture of 9-benzyl-9H-purine-6(lH)-thione, anhydrous K-carbonate, and dimethylformamide, then heated 1 hr. at 40° 3-benzyl-7,8-dihydro-3H-thiazolo[2,3-i]purinium bromide (Y 74%) mixed with p-toluenethiol, K-carbonate, and dimethylformamide, heated 4 hrs. at 75-85° with stirring -> 9-benzyl-l-[2-(p-toIylthio)ethyl]-9H-purine-6(lH)-thione (Y 74%). F. e. s. J. A. Montgomery et al., J. Org. Ghem. 27, 195 (1962). 

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