Naphtho thiadiazines

Unlike naphtho[6c]oxete, described previously, its thio analog 20 is a stable compound which can be obtained in high yield (97-100%) on photolysis of naphtho[c[Pg.8]

Lustrous blue-black crystals of naphtho[l,8-crf][ 1,2,6]thiadiazine (330) were first prepared by Dietz who obtained the sulfoxide (331) by reacting... 

An equimolar ratio of a substrate and oxidizing agent gives oxides 23 and 24 in yields of 71% and 4%, respectively, whereas triple the amount of oxidizing agent leads only to dioxide 24 in 93% yield. The intermediate naphtho[nitrogen elimination even at room temperature. Dioxide 24 may be obtained only on oxidation of monoxide 23, and not via the formation of... 

The first information (37JGU739 67CB2164) about the synthesis of 1,2-dihydrobenzo[crf]indazole by reduction of 1,8-dinitronaphthalene or naphtho[equilibrium with 1,3- and l,5-dihydrobenzo[c[Pg.43]

IJOC4570). Photolysis or thermolysis of naphtho[ c]thiete 20 and naph-tho[carbon disulphide, also occurs by a free-radical mechanism which leads to naphtho[other products of these conversions [79JA7684 81JCS(P1)413]. 

The reaction of peW-diamines with compounds of the type X=S=Y to yield naphtho[l,8-c /][lA4,2,6]thiadiazines, such as 229, has been known for some time [67AG(E)149]. Piperidine- or morpholine-1-sulfenyl chloride have been shown to react with 1,8-diaminoaphthalenes and... 

The PPP configuration analysis technique and the mo ecules-in-molecules/localized configuration interaction (MIM/LCI) method can provide an explanation of the fact that some cyclic sulfur diimides are colorless, while others are not. Thus, while 1,2,5-thiadiazoles 231 and 232 are colorless, naphtho[l,8- /][l 4,2,6]thiadiazine 229 is colored (low intensity absorption at 642 nm). The energy level of the color band appears to be largely determined by frontier orbital interactions. By considering the overlap between the two fragments, (i) the NSN group and (ii) the... 

Ever since the polymer (SN)X was shown to be metallic and to represent the first example of a polymeric superconductor (78JA1235), compounds that contain the NSN group have come under close scrutiny. For instance, the compound naphtho[l,8-corganic solvents. However, despite this apparent stability, the half-wave polarographic potentials of the compound clearly show it is readily oxidized and reduced in acetonitrile. 

The anion-radical of naphtho[l,8-c< ][l,2,6]thiadiazine (277) has been known for several years it has also been the subject of various MO calculations. Recently both the cation-radical (278) and the anion-... 

Inasmuch as naphtho[l,8-Z c]thiete (34) was successively prepared by photolysis and thermolysis of naphthothiadiazine (42), Nakayama et al. (79JA7684) hoped to obtain in the same fashion naphtho[l,8-Z)c]thiete S-oxide (35) from naphtho[l,8-t/c]-1,2,3-thiadiazine S-oxide (50, Scheme 8). They attempted to synthesize sulfoxide 50 by oxidation of thiadiazine (42) with m-chloroperbenzoic acid (m-CPBA). However, this reaction carried out at room temperature with an equivalent amount of m-CPBA occurred with nitrogen liberation and with the formation of naphtho[l, 8-Z)c]thiete S-oxide (35) in 71% yield instead of the expected sulfoxide (50). 

The anion-radical of naphtho[l,8-crf][l,2,6]thiadiazine (277) has been known for several years it has also been the subject of various MO calculations. Recently both the cation-radical (278) and the anion-radical of naphtho[l,8-c,rf 4,5-c (/ ]bis[l,2,6]thiadiazine have been prepared as part of an exploration of the aromatic character, or otherwise, of the heterocycle. (Hyperfine splittings are indicated for 277 and 278 in gauss.)... 

The sulphur-bridged naphthalene (93) has been prepared by photolysis and thermolysis of naphtho[l,8-< ]l,2,3-thiadiazine (94). The presumed intermediate (95) can be intercepted by CS2 to give (96), which is also formed in low yield when (93) is heated or irradiated in CS2. Oxidation of thiadiazine (94) with peracid gives the mono-5-oxide of (93) by spontaneous extrusion of nitrogen from the thiadiazine S-oxide. ... 

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