Trithiane ring

Trithiane readily forms complexes to both soft and hard metal ions and borderline cases. For complexes where X-ray structural information is available, it appears that utilization of S-donor sites in normal tridentate chelation is never attained often the ligand is involved in the form of a bridging mode linking two or more separate metal centers. In addition, the 1,3,5-trithiane ring retains the chair conformer which it possesses in the free state. 

Finally, it is to be mentioned that, along with dithiolethione derivative 253, hexathiaadamantane 254 which contains 1,3,5-trithiane ring moieties has been synthesized from dithiocarboxylic acid derivatives by reaction with CuCl2 and Na2S20s in water <1986IZV1206> (Scheme 74). Structure 254 was assigned unequivocally by NMR spectroscopy and MS. 

Only a few examples of ring syntheses by transformation of another ring have been published. One example is the synthesis of 5-aminomethylene-l,2,3-trithiane 259 from the corresponding 1,3-dithiane derivative 258 <1992M11623> (Scheme 76). The conformation of the substituent on the 1,2,3-trithiane ring, however, was not... 

The second method of synthesis was to allow sodium tetra-sulfide to react with glycerol-a,a -dichlorohydrin in a water-ethanol-chloroform solvent mixture, and introduce three sulfur atoms at once to form v-trithiane ring. In order to synthesize the brugierols from the v-trithiane, it was allowed to act with excess m-chloroperbenzoic acid in chloroform. By doing so, Brugierol and Isobrugierol were obtained in a ratio of 5 to 1. 

A possible mechanism of this oxidative desulfurization is shown in as Fig. 6, namely, the central sulfur atom in the v-trithiane ring is oxidized to form sulfone, in which an intramolecular nucleophillic rearrangement takes place to give the 1,2-dithiolane ring and SO2. The intermediate, 5-hydroxy-l,2,3-trithiane in this reaction is a new v-trithiane compound. And, as we will mention later, it is a compound of importance as the base of insecticidal active derivatives. As there was no report on the crystal structure of v-trithiane, the stereochemical structure was investigated by X-ray analysis. ... 

As the crystals of (1) were unsuitable for X-ray work, the structure analysis was carried out on the crystals of 1,2,3-trithian-5-yl N-methylcarbamate(2) to elucidate the stereochemistry of the v-trithiane ring. 

The various stereochemical informations were supplied by the investigation of the X-ray analysis. For example, the molecule has an approximate mirror plane containing S(2), C(5), and nonhydrogen atoms of planar side-chain. The v-trithiane ring, having almost strict m(Cg) symmetry, assumes a chair form. The side chain at C(5) is equatorial. The interplanar angle of 64 between the... 

TION AND STEREOCHEMISTRY OF 1,2,3-TRITHIANE RING, Chemistry Lettersy 1219 (1978). 

Extension of these studies to medium rings produced interesting results (73). The mercuric acetate oxidation of 1-methyl-1-azacyclooctane (64), when worked up in the usual manner, gave no distillable material. When an equivalent amount of hydrochloric acid was added to the solution which had been saturated with hydrogen sulfide to precipitate the excess mercuric acetate and filtered, evaporation of the solution to dryness gave a solid which was subsequently identified as 2,4,6-tris(6 -methylaminohexyl)-trithiane trihydrochloride (65). Two plausible routes to the observed... 

Thioformaldehyde is unknown in the free state, but polymers of it have been obtained by ring opening of trithiane, by removal of hydrogen sulfide from methanedithiol, by reaction of formaldehyde and hydrogen sulfide or sodium sulfide, and by reaction of sodium hydrosulfide with methylene chloride. The... 

Reaction of acetone with hydrogen sulfide in the presence of acidified ZnCl2 at 25° C gives a good yield of a product composed of60-70% hexamethyltrithiane and 30-40% of 2,2-propanedithiol. Thioacetone can be obtained by pyrolysis of either of these compounds. The trithiane is pyrolyzed either on quartz rings heated to 500-650° C at 5-20 mm (30) or by means of a hot wire (32). The dithiol is pyrolyzed on sodium fluoride pellets heated to 150° C at 11 mm (50). In both cases the pyrolysate is immediately collected in a trap cooled to — 78° C. 

The tobacco alkaloid nicotine (96) (B-67MI10702) is insecticidal by virtue of its action on the acetylcholine receptor. It was used widely as an aphicide, especially as a fumigant. Another natural product thought to act on the same receptor is the 1,2-dithiolane nereistoxin (97) (B-72MI10703), isolated from the marine annelid Lumbriconereis heteropoda. The active form has been shown to be the ring opened dithiol (98), and the protected form of it, cartap (99), is sold as a rice insecticide. The 1,2,3-trithiane thiocyclam (100) (72SAP7007824) is also active, presumably because of metabolic conversion to (98). 

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