Phenyl azide sulfide

Early efforts to effect the photoinduced ring expansion of aryl azides to 3H-azepines in the presence of other nucleophiles met with only limited success. For example, irradiation of phenyl azide in hydrogen sulfide-diethyl ether, or in methanol, gave 17/-azepine-2(3//)-thione35 (5% mp 106—107 " O and 2-methoxy-3//-azepine (11 %),2 3 respectively. Later workers194 failed to reproduce this latter result, but found that in strongly basic media (3 M potassium hydroxide in methanol/dioxane) and in the presence of 18-crown-6, 17/-azepin-2(3//)-one was produced in 48% yield. In the absence of the crown ether the yield of azepinone falls to 35%. 

Attempts to effect ring expansion of methyl 2-azidobenzoate in the presence of other nucleophiles have failed. Thus, photolysis in tetrahydrofuran solution saturated with hydrogen sulfide, or with ammonia, produced methyl 2-aminobenzoate in 54 and 37 % yield, respectively, as the sole identifiable product.197 Photolysis of phenyl azide in ethanolic phenol gave 2-phenoxy-3//-azepine in poor yield (8 %).203,204 2-Mesityl-3//-azepine (10 %) is the surprising, and only tentatively explained, product from the photolysis of phenyl azide in mcsitylene in the presence of trifluoroacetic acid.179... 

A series of alkyl sulfides react with phenyl azide in TFA and TFSA to produce 2- and 4-aminophenyl alkyl sulfides 120 and 121 (Scheme 52). Kinetics results appeared to rule out Sn2 reactions, and the ortho-product... 

Thiocarbonyl S-SulSdes (ThiosulSnes). The formation of the symmetrical 1,2,4-trithiolane (34, eq 14) is the evidence for the intermediacy of thiosulfine 33 formed by a sulfur transfer from thiaziridine 31 to 1. The mixed 1,2,4-trithiolane (51) (eq 22) can result either from the [2 + 3]-cycloaddition of thiobenzophenone 5-sulfide (53) with 1 or from 33 with thiobenzophenone. Both pathways are conceivable for the formation of 51 in a three-component reaction including 1, thiobenzophenone, and phenyl azide. Tetraphenyl-1,2,4-trithiolane (54) undergoes a [2 + 31-cycloreversion and releases 53, which is trapped by 1 to afford 51 (eq 22). The latter is stable under the reaction conditions. ... 

Since nitrene intermediates appear to be ruled out, the photochemical generation of isothiocyanate could either take place via other types of intermediates or directly from a singlet excited state of the thiatriazole. As possible intermediates thiobenzoyl azide, benzonitrile sulfide, and phenylthiazirine were considered.20 Since isothiocyanate is formed from the thiatriazole at 85°K but not from 8 at 85°K where benzonitrile sulfide is stable, the latter was ruled out as a precursor for phenyl isothiocyanate. Thiobenzoyl azide is assumed to absorb in the visible but could not be observed when the thiatriazole was irradiated in an EPA glass at 85 °K, and thus no evidence for its intermediacy was obtained. In conclusion it appears that the isothiocyanate is formed directly from the singlet excited state of the thiatriazole, although the intermediacy of phenylthiazirine cannot be directly excluded. 

The photochemistry of 3-aryl-substituted l,4,2-dioxazol-2-in-5-ones (79) can be interpreted in terms of ring cleavage and loss of carbon dioxide with the formation of an acyl nitrene (80) such nitrenes are also formed by the photolysis of acid azides. In dimethyl sulfide, therefore, the 3-phenyl derivative itself (79 Ar=Ph) is converted into the photoproduct (81).05 When the phenyl group is substituted in... 

AMINATION Azidomethyl phenyl sulfide. Trimethylsilylmethyl azide. 

Azidomethyl phenyl sulfide, C6H5SCH2N3 (I). Mol. wt. 165.22, b.p. 55-58°/0.23 mm, stable to temperatures of 105°. The reagent is prepared from thioanisole by chlorination (S02C12) and azide displacement (NaN3, Nal) 93% overall yield. 

Reaction of ester enolates with trisyl azide and short reaction times at —78° gives the a-azido esters in 50-70% yields 318,413,414 with 4-nitrobenzenesulfonyl azide, the diazo esters are formed almost exclusively.318 Azidomethyl phenyl sulfide and ester enolates give a-amino amides274,275 (Eq. 114),274 but the scope of this reaction has not been determined. 

The only known way to synthesize 3-substituted 6-phenyl-l,4,2-oxathiazines 8 is by ring expansion of 1,3-oxathiolinm salts 7 (see Houben-Weyl, Vol. E8a, p lOff) with azide ions (Method A), iodine/ammonia (Method B) or sulfenamides 11,12 (Method C).47 48 As intermediates, sextet structures of the nitrenium ion or nitrene type are under discussion. It is remarkable that the ring expansion obviously only incorporates the nitrogen function into the C—O bond and therefore only produces 8. 1,4,3-Oxathiazine derivatives, which could equally be formed, were not discovered.48 All three methods A C produce 1,4,2-oxathiazines 8 in yields which are moderate at best. The reaction of 2-dialkylamino-5-phenyl-l,3-oxathiolium perchlorates 7b, 7c with N, V-dimethylthiocarbamoylsulfenamide 11 yields, sometimes even as the main product, also bis(4-pheny -2-dialkylamino-5-thiazolyl) sulfides 9.48... 

Phenylthio)methyl azide, (azidomethyl phenyl sulfide), CftHsSCHiNj (1, 10,14). 

Enantioselective imidation of alkyl aryl sulfides with A -alkoxycarbonyl azides as a nitrene precursor is effected by using (OC)Ru(salen) complex as catalyst. The steric and electronic nature of the Af-alkoxycarbonyl group strongly affect the enantioselectivity and the reaction rate. In a systematic and well-executed study of ligand effects on Lewis-acid-catalyzed Diels-Alder reaction, it has been shown that the attachment of aromatic a-amino acid ligands to copper(II) ions leads to an increase in the overall rate of the Diels-Alder reaction between 3-phenyl-l-(2-pyridyl)-2-propene-l-one (Din) and cyclopentadiene... 

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