Naphthothietes

Naphthothiazole-2-carboxylic acid decarboxylation, 6, 279 Naphthothiene nomenclature, 1, 21 Naphthothiete, S-methyl-reactions... 

The following compounds have been obtained from thiete 1,1-dioxide Substituted cycloheptatrienes, benzyl o-toluenethiosulfinate, pyrazoles, - naphthothiete 1,1-dioxides, and 3-subst1tuted thietane 1,1-dioxides.It is a dienophile in Diels-Alder reactions and undergoes cycloadditions with enamines, dienamines, and ynamines. Thiete 1,1-dioxide is a source of the novel intermediate, vinylsulfene (CH2=CHCH=SQ2). which undergoes cyclo-additions to strained olefinic double bonds, reacts with phenol to give allyl sulfonate derivatives or cyclizes unimolecularly to give an unsaturated sultene. - Platinum and iron complexes of thiete 1,1-dioxide have been reported. 

Phenanthro[4,5-b,c,d]thiophene-4,4-dioxide (20) fragments mainly via the cyclic sulfinate ester15 (Section II.D). Naphthothiete sulfone (65) rearranges also to a cyclic sulfinate (66) prior to fragmentation, as shown by the similarities in their El mass spectra30. The parent SO ion at m/z 308 which was much less pronounced for 65 than for 66 (10 vs. 54%) indicated, however, that the former does not decompose exclusively via 66. 

FVP of benzooxathiinone 126a and naphthooxathiinones 126b-d at 550 °C and 100 Pa through a quartz tube led to the formation of a benzothiete 41 and three isomeric naphthothietes 47-49 in satisfactory yields (Scheme 21) <1996S327>. 

Flash vacuum pyrolysis of 2-(l-benzotriazolylmethyl)-l-thionaphthol 483 produces the naphthothiete from which naphtho[l,2-b]thiopyrans are obtained by reaction with dienes (Scheme 172) <1998JHC1505>. 

Photoelectron spectra of benzothiete 209, the ketene derivative 210, (not isolated), and the naphthothiete 205 have been obtained and vertical ionization potentials reported. The unstable thiolactone 211 shows a carbonyl absorption at 1803 cm . ° The mass spectra of thietes usually show the molecular ion minus a hydrogen atom or other group as the most abundant species, thus suggesting the possible formation of a 4 -electron cation, for example, 212. ° ... 

The first thiete fused to an aromatic system 219 (and an anthracene derivative) was reported in 1965 and was prepared by reduction of a naphthothiete sulfone. An attempt to prepare benzothiete by desulfurization of benzo-l,2-dithiolane was unsuccessful. Photolysis of benzo-l,2-dithiolane 1,1-dioxide in an attempt to extrude sulfur dioxide to give benzothiete also was unsuccessful. The naphthothiete 205, however, was prepared by extrusion of sulfur dioxide from 220 and nitrogen from 221. Thiete 205 also is obtained in 6-8% yield by treatment of 1,8-dehydronaphthalene with carbon disulfide. The unstable thiolactone 211 was formed by a photochemical extrusion of benzaldehyde from 222 and from 222a at 350°C. The benzothietes 209, 223, " and 224 have been... 

Alkyl thietes may be oxidized in low yield to the sulfones with mono-perphthalic acid. An IR absorption at 1067cm suggested the presence of a sulfoxide in the oxidation of 228. Oxidation of the dialkyl thietes 229a and 229b with hydrogen peroxide in acetic anhydride gave 80-85% yields of ,J3-unsaturated aldehydes, possibly derived from an intermediate sulfoxide. The naphthothiete 205 yields either the sulfoxide or sulfone with w-chloroperbenzoic... 

The sulfur atom of naphthothiete 205 may be methylated with trimethyl-oxonium tetrafluoroborate to give the stable salt. 3-Phenylthiete 213 may be alkylated with trimethyl- or triethyloxonium tetrafluoroborate or the trifluoro-methanesulfonate esters The salts are unstable. Alkylation of 218b with methyl iodide gives a ring-opened product, the reaction being facilitated by electron donation from the iron atom. ... 

Methyllithium attacked the sulfur atom of naphthothiete 205 to give 231 and oligomers 232 and 233 via 8-mercaptomethyl-l-lithionaphthalene. Treatment with lithium aluminum hydride followed by methylation gave 234. Treatment of thiete 215 with triphenylphosphine leads to ring-expanded products possibly via nucleophilic attack by phosphorus on sulfur. ... 

The naphthothiete sulfoxide 205a is reduced by lithium aluminum hydride, possibly via a sulfenic acid and a thiolsulfonate intermediate. ... 

Two exomethylene derivatives, 264 and 266, of thiete 1,1-dioxide and three 268a-c of a naphthothiete 1,1-dioxide have been reported. The simplest derivative, 2-methylene-2H-thiete 1,1-dioxide, has not been made. ... 

A different approach was used for the synthesis of the naphtho[ 1,2]thiete 1,1-dioxide 272. The peri-naphthothiete sulfone 20Sb is prepared by photolysis Qf 271612.613 oxidation of the sulfide 205. = ... 

The naphthothiete sulfone 271 undergoes a-hydrogen-deuterium exchange m methanoW catalyzed by sodium methoxide the rate of exchange is essentially the rate of racemization unlike optically active 2-methylthietane 1,1-dioxide in which... 

Refluxing 2,4-diphenyl-2H-thiete 1,1-dioxide in ethanol yields the acyclic sulfone 286. Treatment of naphthothiete sulfone 205b with methyllithium, sodium hydroxide, or lithium anilide gives products, for example, 287, resulting from nucleophilic attack on the sulfur atom of the sulfone... 

Photolysis of naphthothiete sulfone 205b yields principally the disulfone 291 thermolysis yields a small amount of perylene. Thermolysis of the naphthothiete sulfone 267 yields the sultine 292 in the presence of dihydroanthracene in its absence, thiophene derivatives 293 and 294 are formed. ... 

The formation of naphthothiete (34) from dithiol 41 and naphthothiadiazine (42) is preceded by biradical intermediate 43 as proven by the photolysis of naphthothiadiazine (42) in carbon disulfide. After 15 min irradiation alongside naphthothiete (34) obtained in a 52% yield there also formed in a 22% yield naphtho[l,8-<7e]-2,4-dihydro-l,3-dithiin-2-thione (44) resulting from the reaction of biradical 43 with carbon disulfide (Scheme 7). 

The behavior of naphthothiadiazine (42) on thermolysis was investigated. The compound when dissolved in 2-ethoxyethyl ether at 155 °C under a nitrogen atmosphere led to the formation of the expected naphthothiete (34) in 30% yield and three minor products whose structures were not rigorously determined 12% of the initial unreacted compound was also recovered. 

In a still lower yield (1%) naphthothiete (34) was present in the mixture with the other products when 1,8-dehydronaphthalene (40) reacted with diphenyl disulfide (83TL821). 

The reaction of naphthothiete (34) with the lithium aluminum hydride first gives... 

Naphthothiete (34) with methyllithium (McM —McLi, Scheme 10) formed 8-lithio-l-naphthyl methyl sulfide (60, M —Li) that on taking up 1 or 2 equiv of additional 34 was converted into dimer 63 or trimer 64. Sulfide 60 at treating with water formed methyl 1-naphthyl sulfide (62). Dimer 63 was also prepared by an independent synthesis between 60 (M = MgCl) and 1-naphthyl thiochloride (61). 

The reaction of naphthosulfone (36, Scheme 11) with the lithium aluminum hydride takes two directions. The first route consists in reduction to naphthothiete (34) with subsequent transformations represented in Scheme 10 (34—>56—>57—>58 59) on quenching dilithium intermediate 57 with water (R = H). The second path involves opening the hetero ring with the nucleophile without reduction (36—>65 67) also analogous to (34 -> -> -> 59) for naphtho[l,8-Z c]thiete proper (cf. Schemes 10 and 11). Methyl naphthyl sulfone (67) thus obtained was also prepared by an independent synthesis by treating naphtho[l,8-Z c]sulfone (36) with methyllithium followed by quenching with water (36 66—>67). 

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