Acetylene derivs reaction with sulfur

The first stable 1,2-dithiete, 3,4-bis(trifluoromethyl)-1,2-dithiete 527, was reported in 1960, as a result of the reaction of hexafluoro-2-butyne with boiling sulfurother fluorinated derivatives are prepared similarly.The strained acetylene 528 reacts with sulfur to give dithietes. Ring-contraction of 529 with loss of ethylene gives yellow needles of the benzo-1,2-dithiete 526. ° Benzo-dithiete (stable to 180°K) has been obtained by thermolysis of 529a-c or photolysis of 529a. The benzodithiete structure proposed for the product of the oxidation of o-benzenedithiol by iodine is incorrect the material is a polymer. " 3,4-Di-t-butyl-l,2-dithiete is obtained by spontaneous cyclization of the dithione valence tautomer. " ... 

Derivation (1) Condensation of ethylene oxide with hydrocyanic acid followed by reaction with sulfuric acid at 320F (2) acetylene, carbon monoxide, and water, with nickel catalyst (3) propylene is vapor oxidized to acrolein, which is oxidized to acrylic acid at 300C with molybdenum-vanadium catalyst (4) hydrolysis of acrylonitrile. 

Biedermann and Jacobson, who first prepared thieno[2,3-6]-thiophene (1) in 1886, characterized it as a 2,3,4,5-tetrabromo derivative with m.p. 172°. Later Capelle reported the isolation of a dibromo derivative of thienothiophene 1 with m.p. 122.5°, which was shown by Challenger and Harrison to be 2,3,5-tribromothieno[2,3-6]thiophene (m.p. 123°-124°). Capelle also obtained a tetrabromide, m.p. 223°, by bromination of the product of reaction of acetylene with sulfur. The tetrabromide seems to be identical with that prepared from the product of reaction of methane, acetylene, and hydrogen sulfide, m.p. 229°-230°, and is evidently 2,3,5,6-tetrabromothieno[3,2-6j-thiophene. ... 

Rearrangements arc common in reactions of sulfur tetrafluoride with acetylenic and allylic alcohols. Highly acidic acetylenic alcohols derived from hexafluoroacetone and other haloacetones react readily at ambient temperature to give fluorinated allenes 10 as the sole... 

Challenger and co-workers18,19,21,22 first used mercuration (HgClj) to isolate and purify the thienothiophenes from the reaction of acetylene with sulfur. Thieno[3,2-fc]thiophene gave a mixture of mercury derivatives with mercuric chloride both in the presence and in the absence of sodium acetate. The 2-monochloromercury derivative was isolated and converted to the corresponding acylthieno[3,2-h]thiophene with acetyl or propionyl chloride.21,218 The reaction of thienothiophene 2 with mercuric acetate affords the 2-acetoxymercury derivative.20... 

Cyanide (one carbon) and acetylene (two carbons) are limited and other acyl anion equivalents are more versatile. Dithians are thioacetals of aldehydes that can be deprotonated between the two sulfur atoms by strong bases such as BuLi. Reaction with a second aldehyde gives 27 and hydrolysis of the thioacetal by acid, usually catalysed by Cu(II) or Hg(II), gives the a-hydroxyketone 4. The disconnection is that shown on diagram 4 and the lithium derivative 26 acts as the acyl anion 2. Unlike previous methods, R1 does not have to be H or Me. 

Silyl, germanyl and stannyl alk-l-ynyl ketones have been prepared from 2-lithio-2-(trimethylsilylethynyl)-l,3-dioxolane 448. The deprotonation of the dioxane 447 with n-BuLi at — 65 °C afforded the acyl anion 448 which, after reaction with trimethylsilyl, trimethylgermanyl and trimethylstannyl chloride, gave the expected derivatives (Scheme 117)658. Hydrolysis of these products with 0.01 M sulfuric acid at room temperature in aqueous acetone gave the corresponding acyl derivatives 449. On the other hand, the reaction of the intermediate 448 with alkyl halides allows the synthesis of acetylenic ketones659. 

Elimination of the ring s x-orbital delocalization in five-membered heterocycles is a most efficient chemical manipulation used to synthesize highly reactive dienes for Diels-Alder reactions from heterocycles that would otherwise not readily participate in the Diels-Alder reaction. One way to accomplish this goal using heterocycles that contain sulfur atoms is through their oxidation to sulfone derivatives. We will demonstrate the usefulness of this approach by studying the reactivity of 1,3-thiazole 1,1-dioxide and 1,3,4-thiadiazole 1,1,-dioxide as dienes for Diels-Alder reactions with acetylene, ethylene, and cyclopropene. 

By altering the reaction conditions, a preponderance of either product may be produced as desired. Vinyl acetate, which is used for making polymers, and ethylidene diacetate, which is an intermediate for the manufacture of acetic anhydride, are produced on a large scale. The reaction may be applied to other carboxylic adds and acetylene derivatives. Strong acids, such as sulfuric, methane di- and trisulfonic, and phosphoric acids, are catalysts. They may be used in conjunction with mercury salts. Other catalysts which have been disclosed for the reaction include boron trifiuoride and the salts of various metals, such as zinc silicate, zinc acetate, and mercuric phosphate. The addition may be effected in the vapor phase... 

Disubstituted quinolines of type 21 were obtained from acetylenic ketones 2 as a result of a condensation reaction with 2-amino thiophenol 19 followed by sulfur extrusion (entry f). Acetylenic ketones have also been employed as dienophiles in Carbonyl-Alkyne-Exchange (CAE) reactions with dienes 22 (derived from 2,2-dialkyl-2,3-dihydro-4//-pyran-4-ones )(entry g) or 24 (entry h) to yield aromatic compounds 23 and 25 in a highly regioselective way. 

Without additional reagents Reactions of sulfur dichloride with acetylene derivs. 

Numerous unusual organosulfiir transition metal compounds have been obtained by reactions of various metal carbonyls and cyclopentadienyl-metal carbonyls with certain mercaptans, sulfides, disulfides, and dithietenes (1,2). Other types of organosulfiir transition metal compounds have been obtained from metal sulfides and certain acetylene derivatives (3). This paper discusses a new and entirely different synthesis of new types of organosulfur derivatives of metal carbonyls with metal-sulfiir bonds. These new compounds have been obtained by thermal or photochemical decarbonylation of compounds of general formula CH S CH ) U(CO)yHC H )y (n = 1,2 or 3 M = Fe [x 2, y = 1], or Mn [x = 5, y = OJ) without metal-sulfur bonds. These sulfur-containing transition metal alkyl derivatives, none of which has been previously reported, may in turn be obtained from metal carbonyl anions and the chloroalkyl methyl sulfides CH S(CHpnCl. 

This chapter concerns selected reactions discovered in years, 2000-2012 initiated by the availability of some unusual acetylene derivatives. These reactions have led to the creation of novel carbocyclic and heterocyclic compounds. Historically, most of the studies were performed by, or with the participation of, Russian researchers. The cycloaddition reactions include various pathways to cyclobutene and cyclohexadiene derivatives, the heterocyclization reactions have demonstrated additional pathways to various nitrogen- and sulfur-containing heterocycles. 

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