Bis trimethylsilyl Sulfide

Akiya Ogawa Noboru Sonoda Osaka University, Osaka, Japan 

Solubility sol diethyl ether, THF, CH2CI2, MeCN, and aromatic solvents. 

Form Supplied in colorless cloudy liquid, commercially available. 

Sulfur Transfer Reagent Alkyl sulfides can be formed from the corresponding alkyl halides using TMS2S. Thioaldehydes, thioketones (eq 3), thioamides, thioacid anhydrides, thioacyl-silanes, divinyl sulfides (eq 4), and thiranes (eq 5) are also produced from TMS2S and their respective carbonyl or alkenic compounds, in combination with the reagents shown. 

Silicon Transfer Reagent Bis(trimethylsilyl) sulfide can transform alcohols, acids, and amines into their silylated counterparts. Enol silanes are also formed under the influence of this 

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Another reagent system that has been recently employed in the Paal synthesis of thiophenes is the combination of bis(trialkyltin)- or bis(triaryltin) sulfides with boron trichloride. Known as the Steliou reagent,it has been utilized in the transformation of 1,4-diketone 11 to thiophene 12. Higher yields are obtained in shorter reaction times in contrast to the use of Lawesson s reagent. Additionally, others have noted the relative ease of the work-up procedure using the Steliou conditions, and the fact that the tributyltinchloride byproduct of the reaction is reusable. Similarly, the combination of the bis(trimethylsilyl)sulfide has been used in conjunction with trimethylsilyltriflate for the preparation of thiophenes in an analogous manner. ... 

Aldehydes can be converted into thioaldehydes by a similar reaction with bis(trimethylsilyl) sulfide catalyzed by BuLi (equation II). This disilyl sulfide has been used indirectly for conversion of aldehydes into thioaldehydes via boron trisulfide (11, 63). 

Capperucd and co-workers investigated the dimerization of a,/i-un saturated thioacylsilanes 224, which are generated in situ from 1-silylated alkoxyallenes 222 using bis(trimethylsilyl) sulfide and cobalt(II) chloride hexahydrate as reagents. The resulting 1,2-thiins 223 are isolated as major products in 29-65% yield [128] (Scheme 8.55). 

The reaction of tra i -[ Me3N(H)Al( j,-Se) 2] with N,N,N, N",N"-ptnia-methyldiethylenetriamine (PMEDTA) affords an interesting bicyclic compound with an AUScs (9.33b) skeleton the sulfur analogue of this bicycle 9.33a is obtained from the direct treatment of Me3N AIH3 with bis(trimethylsilyl) sulfide at 90 °C in toluene (Scheme 9.20). ... 

Treatment of bis(trimethylsilyl)sulfide (8) with bromine in anhydrous dichloromethane at - 78°C followed by addition of 1,2-disubstituted alkenes (9) to the reaction mixture at the same temperature gave the thiiranes (10) in about 30% yields (Scheme 5) (88TL4177). This synthesis is (i) highly selective, since only 1,2-disubstituted alkenes undergo the transformation to thiiranes and (ii) stereospecific since the stereochemistry of the alkene is retained in the thiirane. The nature of the reagents suggests that the silyl subsituted sulfenyl bromide (11), formed by attack of bromine on (8), is an intermediate. 

Methyl methylthiosulfinate (lg, 9 mmol) was dissolved in anhydrous chloroform and treated with bis(trimethylsilyl) sulfide (1.62 g, 9 mmol). The reaction mixture was heated to 60CC with stirring for 14 h, diluted with dichloromethane and washed several times with water. After work-up the crude material obtained was distilled under vacuum to obtain the pure trisulfide (830mg, 73%), b.p. 65-68°C725 torr. 

A solution of the aldehyde (1 mmol), the diene (1.5 mmol) and bis(trimethylsilyl) sulfide (2 mmol) in acetonitrile (0.5 ml) was treated at room temperature with a solution of CoC12.6H20 (0.2 mmol) in acetonitrile (2.5 ml). Progress of the reaction was monitored by GC/MS analysis. The reaction mixture was quenched with saturated ammonium chloride, extracted with ether and dried over sodium sulfate, and the solvent removed under vacuum. The crude reaction product was then purified by column chromatography or TLC on silica gel. For R1 = Ph a 94% yield was secured. 

Thiiranes can be formed directly and stereospecifically from 1,2-disubstituted alkenes by addition of trimethylsilylsulfenyl bromide, formed at -78 C from reaction of bromine with bis(trimethylsilyl) sulfide (Scheme 7).12 A two-step synthesis of thiiranes can be achieved by addition of succinimide-A/-sulfe-nyl chloride or phthalimide-A -sulfenyl chloride to alkenes followed by lithium aluminum hydride cleavage of the adducts (Scheme 8).13 Thiaheterocycles can also be formed by intramolecular electrophilic addition of sulfenyl chlorides to alkenes, e.g. as seen in Schemes 914 and 10.13 Related examples involving sulfur dichloride are shown in Schemes 1116 and 12.17 In the former case addition of sulfur dichloride to 1,5-cyclooctadiene affords a bicyclic dichloro sulfide via regio- and stereo-specific intramolecular addition of an intermediate sulfenyl chloride. Removal of chlorine by lithium aluminum hydride reduction affords 9-thiabicyclo[3.3.1]nonane, which can be further transformed into bicyclo[3.3.0]oct-1,5-ene.16... 

Another reagent with limited application in thionation reactions has been S2CI2, which afforded intermediates leading to 1,3,4-oxadithiolanes300. However, among the different thionating reagents developed in recent years the most successful has been bis(trimethylsilyl) sulfide, which in the presence of a catalyst affords thioaldehydes... 

Treatment of aryl and heteroaryl o-azidocarbaldehydes with bis(trimethylsilyl)sulfide and hydrochloric acid gave fused isothiazoles, via thionation of the formyl function followed by spontaneous decomposition at room temperature. Yield was dependent upon the nature of the heteroaromatic ring. [94CL1873, 94PS479]... 

An attractive reagent for the transformation of ketones into thioketones has been introduced by Degl Innocenti and co-workers [74, 75]. The commercially available bis (trimethylsilyl) sulfide works efficiently at room temperature, with catalysis of CF3S03SiMe3 in acetonitrile, for the production of aromatic thiobenzophenones, adamantanethione and 2-cyclenethiones. 

The thionation of aldehydes with bis(trimethylsilyl)sulfide and CoCl2.H20 in the presence of a 1,3-diene was applied to pyruvaldehyde (Table 3, entry 3). In the presence of TMSOTf a remarkable stereochemical effect was observed one equivalent of the Lewis acid leads to a 97 3 endo exo mixture, whereas two equivalents furnish selectively the exo isomer [74]. 

RCOSi(CH3)3 — RCSSi(CH3)3.1 Acybi lanes by reaction with bis(trimethylsilyl) sulfid yield). The reaction is also applicable to al thioaldehydes, which can be trapped by diem... 

Dithiins 367 have been prepared in moderate yields by [4 + 2] cycloaddition of in situ formed thioenones with thiocarbonyl groups (Scheme 171) <2004SL2159, CHEC-III(8.11.9.2)824>. The thio compounds were generated from trialkylsilyl- or trialkylstannyl-tetrahydropyranyloxy allenes 366 using bis(trimethylsilyl)sulfide (HMDST) and CoC nbE O. 

Sulfuration of 2,3-diaroylbicyclo[2.2.1]hepta-5-enes 50 using B2S3, which is generated in situ by reaction of BCI3 with bis-trialkyltin sulfide or with bis-trimethylsilyl sulfide, produces enthiols 51 and 52. Their cyclizations followed by [3,4] and [3,5] rearrangements afford dihydrothiophene 53 and thiophene 54, respectively (Scheme 12) <1997TL799>. 

Bis(trimethylsilyl) sulfide reacts with methyl, phenyl, or other thiosulfinates (disulfane oxides), R S(0)SR, in anhydrous chloroform at 60 °C to give the symmetrical trisulfane and hexamethyldisiloxane the latter is removed together with the solvent by vacuum distillation, leaving almost pure R2S3 (yields 70 90%). In a similar reaction,... 

Unsaturated thialdehydcs, generated from the corresponding aldehydes by treatment with bis(trimethylsilyl) sulfide in the presence of butyllithium, undergo intramolecular Diels-Alder reaction affording cycloadducts 3 as a mixture of cis- and trans-fused isomers62. 

Segi et al. reacted some aldehydes with bis(trimethylsilyl) sulfide in THF with n-BuLi as catalyst. The thioaldehydes (41) thus formed were trapped with cyclopentadiene to afford adducts 42 as a mixture of endo and exo isomers (88JA1976). French workers have recently reported a gas-phase synthesis of thioxoethanal (44) from precursor (43) 44 was detected as an intermediate by photoelectron spectroscopy and by the formation of adduct 45 (90JOC2596). 

The reaction of a 1,4-dicarbonyl compound (cf. 16.16.1.1 and 18.13.1.1) with a source of sulfide, traditionally phosphorus sulfides, latterly Lawesson s reagent (LR), " or bis(trimethylsilyl)sulfide, " gives thiophenes, presumably, but not necessarily, via the bis(thioketone). 

It was found that sulfuration of 1,4-dicarbonyl compounds with bis(trialkyltin) and bis(triphenyl-tin) sulfides in the presence of boron trichloride provides a new thiophene synthesis <92JOCl722>. Particularly, sulfuration with bis(tributyltin) sulfide proceeds at room temperature to give the corresponding thiophenes (327) in high yields (Equation (62)). Trifluoromethyl trifluoromethane-sulfonate-promoted bis(trimethylsilyl) sulfide sulfuration also converts 1,4-dicarbonyl compounds (328) to the thiophenes (329) in moderate yields (Equation (63)) <94JOC3695>. 

Hexamethyldisilthiane or bis(trimethylsilyl)sulfide, (Me3Si)2S, is a colourless, moisture-sensitive, flammable liquid (b.p. 160 °C) with a strong stench, ft was first prepared from trimethylsilyl chloride and silver sulfide by Eaborn in 1950 but cheaper, more convenient syntheses facilitated its commercial production. The compound has many applications in organic synthesis, e.g. reduction, sulfuration and silylation reactions and in the production of metal sulfide-based electronic devices, semiconductors, nanoparticles and quantum dots. ... 

Bis(trimethylsilyl) sulfide (hexamethyldisilathiane) [3385-94-2] M 178.5, b 65-67°/16mm, 162.5-163.5°/750mm, 164°/760mm, d 4 0.85, n 1.4598. Dissolve it in petroleum ether (b ca 40°), remove the solvent and distil it. Redistil it under atmospheric pressme of dry N2. It is collected as a colourless liquid which solidifies to a white solid in Diy-ice. On standing for several days it turns yellow possibly due to liberation of sulfur. Store it below 4° under dry N2. [Eabom J Chem Soc 3077 1950, Beilstein 4 IV 4033.]... 

A convenient and stereoselective, synthetic route was reported for the preparation of 3,7-disubstituted-l,2,5-trithiepanes 209 by the reaction of thiiranes with bis(trimethylsilyl)sulfide (HMDST) followed by intramolecular oxidative cyclization (14HAC678). In the reaction of substituted etha-nolamines with formaldehyde, the desired bis(oxazolidin-3-yl)methanes were prepared as a mixture of products, the ratio of the isomeric 3,8-dioxa-l,6-diazabicyclo[4.4.1]undecane 210 product present was dependent on the substituent on the ethanolamine (14CHE726). Whether the bis(oxazolidin-3-yl)methanes were isolated or the mixtures were taken on for further reaction, the subsequent product was formed exclusively. 

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