4-Aryl thio

If greater activation is desired the methyl- or aryl-thio derivatives may be oxidized to the sulfoxides/sulfones (Section 2.15.4.1), which may then be aminated (64JOC2903, 80JOC3746, 77JOC997). 

In addition, Suehiro et al. (1987) were able to accurately determine the rates of dediazoniation of twenty substituted aryldiazenyl radicals formed from aryl(aryl-thio)diazenes (Scheme 8-36), in cyclopropane and in alkenic solvents at -48 to — 117°C, using a time-resolved ESR method. 

Bei —0,75 bis —0,95 V entstehen dagegen in verdiinnter Schwefelsaure quantitativ die Aniline. Somit kann offenbar mit Hilfe der Spannung die Reduktion eindeutig gelenkt werden. Hierfiir ist aueh die Reduktion von 3-Nitro-benzoesaure4 bzw. 4-Nitro-l-al-kyl(aryl)thio-benzols Beweis ... 

Some alkyl and aryl-thio compounds are known, most being prepared by nucleophilic displacement of halo or nitro groups. Examples of furazans fused to dithianes have also been described bis-furazan (75) can be prepared either by dehydration of the tetraoxime or by reaction of potassium thiocyanate with dinitrofurazan <95MI 405-03). 

This reaction is analogous to 0-16. Primary and secondary alcohols can be converted to alkyl aryl sulfides (ROH —> RSAr) in high yields by treatment with Bu3P and an N-(aryl-thio)succinimide in benzene.759 Thioethers RSR can be prepared from an alcohol ROH and a halide R Cl by treatment with tetramethylthiourea Me2NC(=S)NMe2 followed by... 

S. Hanessian and Y. Guindon, Chemistry of the glycosidic linkage. Direct conversion of glycosides into 1-thioglycosides by use of [alkyl (or aryl)thio] trimethylsilanes, Carbohydr. Res. 86 C3 (1980). 

The enol phosphate 191 (R / H) has been widely used in the preparation of a large number of carbapenems having a 2-allyl- or aryl-thio substituents. The reaction is promoted by the presence of base and the choice of solvent is important. Diisopropylamine or dicyclohexylamine tend to give better results than tertiary amines and nonnucleophilic bases such as... 

Tau P, Nyokong T (2006) Synthesis, electrochemical and photophysical properties of phthalo-cyaninato oxotitanium(IV) complexes tetra substituted at the a and fi positions with aryl thio groups. Dalton Trans (37) 4482-4490... 

Tau P, Nyokong T (2007) Electrocatalytic activity of aryl thio tetra substituted oxotitanium(IV) phthalocyanines towards the oxidation of nitrite. Electrochim Acta 52(13) 4547-4553... 

Die analoge Addition von aliphatischen u. aromatischen Sulfensaure-chloriden an Propa-dienphosphonsaure-diester bei -10° und anschlieBende RingschluBreaktion zu 2-Alk-oxy-4-alkyl(aryl)thio-2,5-dihydro-l,2-oxaphosphol-2-oxiden bei 20° gelingt ebenfalls in Ausbeuten von 65-80%480-... 

Title V-Aryl (thio) Anthranilic Acid Amide Derivatives, Their... 

Thiolate anions and oxime aUcoxides react under phase transfer conditions to give aryl thio ethers and O-aryl oximes, respectively the o-dichlorobenzene complex can be converted selectively to the monosubstitution product (equation 97). 

Petropoulos (28) observed that the ring-substituted compounds (see above) were more efficient photoinitiators than desyl phenyl sulphide itself, and suggested that resonance stabilisation of the aryl thio radical might be important in increasing the rates of dissociation. 

The following discussion includes removal of a variety of sulfur substituents, including not just alkyl-and aryl-thio (RS), but also sulfinyl (RSO), and sulfonyl (RSO2) groups a to carbonyl groups. 

By careful control of metallating agent, blocking groups and reaction conditions, it is possible to make 2-alkyl(aryl)thio- and 4(5)-alkyl(aryl)thioimidazoles in high yields, e.g. l-trityl-2-phenylthio- [3], 4(5)-methylthio- [4] and l-benzyl-2,4,5-tris(methylthio)-imidazole [5]. 

Vinyl sulfides undergo smooth addition of dichlorocarbene to yield 2-alkyl(or aryl)thio-l,l-di-chlorocyclopropanes. Investigation of the relative activities towards dichlorocarbene shows that vinyl sulfides are five to six times more reactive than the corresponding vinyl ethers. 

The effective charge on the sulfur atom in the displacement of an aryl-thio group from an alkyl donor is -0.16 units. The change in effective charge, Ae, is therefore +0.84 from arylthio anion to thioether (Scheme 7). 

A series of 2-alkyl(aTyl)thio-3//-quinolin-4-ones 120 were synthesized in a thermally induced cyclization <05OL5281>. Initially, the ketenimine 121 undergoes a [1,5] sigmatropic migration of the alkyl(aryl)thio group to form 122 followed by a 67t-electrocyclic ring closure resulting in the formation of 120, illustrated in Scheme 34. 

The wH/f-selective reduction of a-alkylthio ketones is less straightforward. Zinc borohydride has been used successfully in some cases, implying that chelation control involving an alkyl(or aryl)thio group is possible. However, the method is not general, as illustrated by the results in the zinc borohydride reductions of 3-methyl-2-methylthio-l-phenylbutanone and 4-methyl-3-phenyl thio-2-pentanone 81. 

Lactones may in principle be obtained if the olefinic trap is placed on the oxygen side of the xanthate. The more complex sequence in Scheme 11, discovered seren-dipitously, illustrates the construction of such a lactone starting with an aryl thio-carbonate [20]. It also involves the transfer of the aryl group in the penultimate step. 

Alkoxy-l, 3-benzodithiole, die in einfacher Weise aus 2-Diazo-benzoesaure und Schwefel-kohlenstoff in Gegenwart von Alkanol erhalten werden377, setzen sich mit prim., sek. oder tert. Alkanthiolen sowie Thiophenolen in Essigsaure tiber 1,3-Dithiolanium-Ionen auBer-ordentlich rasch zu 2-Alkyl(Aryl)thio-l,3-benzodithiolen um378 ... 

Tab. 20 1,1,1 -Tris-[organothio]-alkane aus metallierten Tris-[alkyl(aryl)thio]-methanen durch elektrophile Substitution... 

---