Thiets

Thiets.—Thiete (111a) and its simple derivatives e.g. 111b) were prepared some years ago they are labile and tend to polymerize. The corresponding 1,1-dioxides 2ire considerably more stable. Stabilization of thiete by annelation with a benzene ring has now been achieved with the synthesis of (114), prepared by the photolysis of (112) the isomer (113) was obtained by acid hydrolysis of (112).  

The syntheses of five thiets (169) via the cycloadducts of sulphenes to enamines have been reported. They are thermally unstable and undergo 

Treatment of thiets with di-iron enneacarbonyl yields complexes, e.g. (177), of thioacrolein. X-Ray analysis of thioacrolein triphenylphosphine dicarbonyliron (178) established the structure.  

The magnitudes and signs of all C-H and H-H coupling constants for thiet 1,1-dioxide have been determined, and its microwave spectrum has been recorded.  

The synthesis and properties of optically active thiet 1,1-dioxides have been reviewed. The generation of sulphenes from p-nitrophenyl sulpho-nates is claimed to have advantages in the preparation of 3-amino-4-arylthiet 1,1-dioxides from acetylenic amines, principally in the avcndance of the presence of triethylamine hydrochloride, which is believed to cause isomerization of the thiet derivative. Several other thiet dioxides have been obtained by reaction of a sulphene with an acetylenic amine. - They are claimed to be anti-inflammatory agents. The formaticm of a thiet 1,1-dioxide from acetylenic sulphine (167) and an enamine has been noted previously. A number of substituted thiet dioxides have been prepared by addition of sulphene to enamines followed by a Cope elimination of the amine. These compounds were tested for analgesic activity but none was found. Thiet 1,1-dioxide (123) is obtained from 

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The participation of a single double bond of a heterocycle is found in additions of small and large rings azirines (Section 5.04.3.3) and thietes (Section 5.14.3.11) furnish examples. Azepines and nonaromatic heteronins react in this mode, especially with electron deficient dienes (Scheme 16 Section 5.16.3.8.1). 

Spiro[4- t-butyl-3-methylthio]thiete-2,9 -xanthene X-ray, 7, 407 (80AX(B)484>... 

Thiabicyclo[3.1.0]hex-3-ene synthesis, 4, 784 9-Thiabicyclo[3.3.1]nonane 9,9-dioxide bond angles, 7, 409 5-Thiabicyclo-2-pentene, 1,2,3,4-tetrakis(trifiuoromethyl)-rearrangement, 7, 153 2H-l,2-Thiaborin dibenzo fused, 1, 658 1-Thia[2.2.2]cyclazines, 4, 479 5-Thia[2.3.3]cyclazines, 4, 481 Thiacyclobutadienes — see lH-1 A -Thietes... 

THIETE 1,1-OIOXIDE AND 3-CHLOROTHIETE 1,1-DIOXIDE (2H-Thi ete l,l-d1oxi[Pg.210]

C. Thiete 1,1-dioxide. A sample of 3-chlorothietane l,l-d1ox1de (8.0 g, 0.057 mol) Is dissolved In dry toluene (300 ml) (Note 7) In a 500-mL, twonecked, round-bottomed flask equipped with a reflux condenser, magnetic stirrer, heating mantle (or silicone oil bath), and thermometer. The reaction Is heated to 60° C and tri ethyl amine (28.7 g, 0.28 mol, 39,5 ml) Is added through the condenser. The reaction mixture Is stirred for 4 hr and triethyl-amine hydrochloride is removed by filtration and washed with toluene (100 mL), Toluene is removed on a rotary evaporator and the residue is recrystallized from diethyl ether-ethanol (Note 8) to give a white solid (4.5-4.8 g, 75-81 ) mp 49-50°C (llt mp 52-54°C). 

This preparation of thiete 1,1-dioxide is more direct and less tedious than previous methods. 

Conversion of 3-chlorothietane 1,1-dioxide to the 3-(N,N-dimethylaraino) derivative followed by reduction, quaternization, and Hofmann elimination affords a convenient route to the highly reactive thiete (thiacyclobutenel... 

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. 

Chloroth1ete 1,1-dioxide is a potentially useful intermediate for the preparation of other 3-substituted thiete 1,1-dioxides via addition-elimination reactions. 

C3H402S, 2H-Thiete 1,1-dioxide C4H602S, 2,5-Dihydrothiophene 1,1-dioxide C4H602S, 2,3-Dihydrothiophene 1,1-dioxide CsHgOjS, 2,5-Dihydro-2-methylthiophene 1,1-dioxide C5H802S, 2,5-Dihydro-3-methylthiophene 1,1-dioxide... 

To date, all saturated and unsaturated three- and larger-membered ring sulfones and sulfoxides (e.g., thiirane (3), thiirene (4), thietane (5), thiete (6), dithietane (7), thiolane (8), thiolene (9), thiane (10), thiene (11), dithiane (12), thiepane (13), thiocane (14), and their unsaturated analogues as well as isomers and closely-related systems) have been synthesized and their chemistry well-established. 

In view of the limited capacity of the sulfur atom in the sulfoxide and sulfone functional groups to transmit conjugative effects due to the insulating effect of the LUMO sulfur d-orbitals45,46,56, the application of the UV technique even in the case of the cyclic vinyl sulfones (e.g. thiete dioxides 6b) cannot be expected to find extensive use. UV spectra of substituted thiete dioxides in which an extended conjugated system (e.g. 194) exists in the molecule, did provide useful information for structure elucidation231. However, the extent... 

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