Thioketenes thiols

The reactive thiol/thioketene produced by the (3-lyase is an alkylating fragment, which binds to protein, DNA, and GSH. The fact that one of the locations of C-S lyase is in mitochondria may explain why this organelle seems to be damaged. Damage to the respiratory chain will lead to depletion and a shortage of ATP, which is vitally necessary for the activity of the kidney in terms of active uptake and secretion. 

Thio-Claisen rearrangement 746-748 Thioketene 5-oxides photolysis of 878 reactions of 277 Thiolane dioxides formula of 382 NMR spectra of 460 reactions of 604 synthesis of 461 Thiolane oxides 747 formula of 382 IR spectra of 461 synthesis of 461, 462, 752 Thiolanes, photolysis of 881 Thiolene dioxides formula of 382 NMR spectra of 460 reactions of 464, 465 synthesis of 461 Thiolene oxides formula of 382 synthesis of 461, 746 Thiols... 

The enolates of other carbonyl compounds can be used in mixed aldol reactions. Extensive use has been made of the enolates of esters, thiol esters, amides, and imides, including several that serve as chiral auxiliaries. The methods for formation of these enolates are similar to those for ketones. Lithium, boron, titanium, and tin derivatives have all been widely used. The silyl ethers of ester enolates, which are called silyl ketene acetals, show reactivity that is analogous to silyl enol ethers and are covalent equivalents of ester enolates. The silyl thioketene acetal derivatives of thiol esters are also useful. The reactions of these enolate equivalents are discussed in Section 2.1.4. 

Silyl acetals of thiol esters have also been studied. With TiCl4 as the Lewis acid, there is correspondence between the configuration of the silyl thioketene acetal and the adduct stereochemistry.314 L-Isomers show high anti selectivity, whereas Z-isomers are less selective. 

Thioacylation of Thiols with Thioacyl Halides, Thioacyl Anhydrides and Thioketenes... 

Stable, as well as transient, thioketenes give dithiocarboxylic esters on reaction with thiols (equation 61). ... 

Laureni and co-workers have studied the photochemical decomposition of 1,2,3-selena and 1,2,3-thiadiazoles in argon or nitrogen matrix. In each case they could identify the products as the ethynylselenol or thiol (136) and the seleno-or thioketene (137). In addition, in the case of 1,2,3-selen-adiazole acetylene was also detected. Using isotopically labelled substrates, they demonstrated that a major portion of the ethynylthiol formed from 1,2,3-thiadiazoles must have undergone an equilibriation of the carbons, probably through the symmetrical thiirene intermediate (138). In the case of the selenium compound, however, their results showed that the selenirene is not on the route to the ethynylselenol (136, X = Se). 

A further extensive paper and two associated patents have revealed more of the interesting chemistry of bis(trifluoromethyl)thioketen. The reactions encompassed by these publications include additions of water, alcohols, thiols, hydrogen bromide, primary and secondary amines, NN-dimethylanilines, ethers, and silicon and tin hydrides (Scheme 30), as well as an extensive series of ene reactions (Scheme 31). 

The additions of active-hydrogen compounds to the thioketen are believed to proceed via ene-thiols ... 

In contrast, dimerization of monoalkyl thioketenes affords 2-aIkyIidene-1,3-thiols 4... 

Thioketens, which are now more readily available 27-429 tt n some years ago, are valuable reagents for the thioacylation of alcohols and thiols at room temperature. The thioketen (183), which is formed from the thioaldehyde (182)... 

Raasch has extended his studies of the reactivity of bis(trifluoro-methyl)thioketen (141). Scheme 8 gives a survey of the reactions that have been carried out. Thus common nucleophilic agents such as alcohols, thiols, primary, and secondary amines, etc., react with (141) with conservation of the C=S double bond, whereas the C==C double bond remains in the products of the reactions of (141) with certain ethers, dimethylaniline, and hydrides of tin and silicon. Compound (141) reacted with a variety of olehnic substances in accordance with the general ene-reaction formalism, yielding allyl vinyl sulphides (148). The formation... 

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