Thiirane Derivatives Research Articles

Reaction of N,N‐Disubstituted Polyfluoroalkanethioamides with Diazomethane: Entry to New Thiirane Derivatives

New fluorinated thiirane derivatives were formed as a result of the reaction between N,N‐disubstituted polyfluoroalkanethioamides and diazomethane. The obtained thiiranes were smoothly desulfurized by the treatment with triphenylphosphine affording 1‐polyfluoroalkyl enamines. New transformations of the synthesized thiiranes and enamines into functionalized 1,4‐dioxanes have been found to occur under the action of m‐chloroperoxybenzoic acid. The structures of 1,4‐dioxanes containing trifluoromethyl and pentafluoroethyl groups have been determined by X‐ray diffraction analysis.

Functionalization of soy fatty acid alkyl esters as bioplasticizers

The combination of various functional groups, such as epoxy, acetoxy, methoxy, thiirane, and aziridine, on the fatty acyl chain of soy fatty acid alkyl esters have been synthesized and evaluated as plasticizers in poly(vinyl chloride) (PVC) applications. Numerous synthetic procedures, such as epoxidation, methoxylation, acetylation, thiiration, and aziridination, were used for synthesizing multifunctional soy fatty acid alkyl esters. Epoxidized soybean oil fatty acid alkyl ester served as the key intermediate for functionalization. Partial or complete ring opening of the epoxide by reacting with methanol and the subsequent etherification or acetylation of the hydroxyl function produced epoxy, alkoxy, and acetoxy derivatives. The nucleophilic substitution of epoxide with sulfur by reacting with ammonium thiocyanate produced thiirane and epoxy thiiranes. Although the aziridine derivatives were synthesized by reacting unsaturated fatty acid alkyl esters with chloramine‐T, the compounds were fully characterized and their physical and analytical properties were determined. The high viscosity and darker color of aziridine and thiirane derivatives limit their usefulness, whereas the physical properties of the other derivatives were acceptable. The plasticizer evaluation of methoxy and acetoxy soy fatty acid esters (methyl and n‐butyl) demonstrated good compatibility with PVC, high efficiency (Shore hardness), and gelling properties were comparable to commercial plasticizer, di‐isoonyl phthalate. The abundant availability and cost‐effectiveness of starting materials and the readily adoptable chemical processes make the fatty acid ester derivatives viable bioplasticizers to replace the fossil fuel‐derived phthalates. J. VINYL ADDIT. TECHNOL., 23:93–105, 2017. © 2015 Society of Plastics Engineers

BIOLOGICAL OVERVIEW ON THIIRANE DERIVATIVES

The thiirane moiety is an important substance and shows some important biological activities. Recently, much attention has been focused on thiirane derivatives for their scarcity of their pharmacological activities. Various substituted thiirane derivatives have also been reported to show cytotoxic properties. The combination of two or more heterocyclic and non-heterocyclic systems enhances or other substitution affects their biological profile better than parent nuclei. We consider some compounds bearing thiirane in their molecular framework.

New clicked thiirane derivatives as gelatinase inhibitors: the relevance of the P1′ segment

Gelatinases (MMP-2 and MMP-9), a subfamily of Matrix Metalloproteinases (MMPs), are involved in several pathologies and especially in cancer. Thiirane is a latent-zinc binding group used for the design of potent inhibitors of gelatinases. Here we report a new family of thiirane inhibitors, obtained by click chemistry. Thus, an azide fragment containing the thiirane group was connected to several lipophilic alkynes, which were designed to interact with the S1′ pocket of the two gelatinases. Our hit compound (2f) displayed submicromolar inhibition of MMP-2 (IC50 = 0.62 μM). Computational studies have been used to compare the binding mode of compound 2f in MMP-2 with the reference thiirane inhibitor (SB-3CT), allowing us to discuss the relevance of the P1′ segment in order to maximize potency.

ChemInform Abstract: Recyclization of Benzimidazo[2,1‐b]thiazanium Salts into 1‐(2,3‐Epithiopropyl)benzimidazol‐2‐ones under the Action of Epichlorohydrin.

AbstractThe proposed method enables the introduction of functional groups unstable in alkaline medium into the structure of thiirane derivatives.

ChemInform Abstract: Tetrathiomolybdate Mediated Rearrangement of Aziridinemethanol Tosylates: A Thia‐aza‐Payne Rearrangement.

AbstractThe rearrangement affords thiiranes.

Tetrathiomolybdate Mediated Rearrangement of Aziridinemethanol Tosylates: A Thia-Aza-Payne Rearrangement

Aziridinemethanol sulfonate esters react with tetrathiomolybdate 1 to give thiirane derivatives as the major product and cyclic disulfides as minor product under mild reaction conditions via an unprecedented thia-aza-Payne-type rearrangement. Interestingly, when the reaction of 1 was carried out with 2-aziridino-cyclohexanol derivatives it resulted in the formation of thia-bicyclo[3.1.1]heptane or dithia-bicyclo[3.2.1]octane derivatives.

Recyclization of benzimidazo[2,1-b]thiazanium salts into 1-(2,3-epithiopropyl)benzimidazol-2-ones under the action of epichlorhydrin

It has been shown that the reaction of epichlorhydrin with 3-hydroxybenzimidazo[2,1-b]thiazanium salts leads to recyclization of the thiazanium ring with the formation of substituted 1-(2,3-epithiopropyl)benzimidazol-2-ones in high yield. The proposed method enables the introduction of functional groups unstable in alkaline medium into the structure of thiirane derivatives.

Circular Dichroism and Absorption Spectroscopy for Three-Membered Ring Compounds Using Symmetry-Adapted Cluster-Configuration Interaction (SAC-CI) Method

Abstract The singlet excited states of oxirane and thiirane derivatives, ethylene oxide, (R)-methyloxirane, (2S,3S)-dimethyloxirane, ethylene sulfide, (R)-methylthiirane, and (2S,3S)-dimethylthiirane, were calculated employing the symmetry-adapted cluster (SAC)/SAC-configuration interaction (CI) method. The rotatory strengths of the CD spectra were calculated in the velocity form, which is gauge-origin independent. Both the ultraviolet (UV) spectra and the circular dichroism (CD) spectra obtained with the SAC-CI method were in good agreement with the experimental spectra. In oxirane derivatives, the low-lying excited states were composed of excitations from n and σ orbitals to s, p, and d Rydberg orbitals. The excitation from the σ orbital was especially important in (2S,3S)-dimethyloxirane because of the steric effect of the methyl substitutions. However, in thiirane derivatives, the excitations to the low-lying excited states were only from the n orbital.

Molecular structure and thermal stability of α-halogen-gem-dithiols

The electronic structure of α-halogen-gem-dithiols RC(SH)2CH2X (R = Me, Ph; X = F, Cl, Br, I) was studied by quantum chemistry methods. Four most stable rotamers were located, differing in the mutual orientation of the thiol groups and the halogen atom. The thermodynamic and kinetic characteristics of the thermolysis of α-halogen-gem-dithiols were obtained. Thermolysis of chlorine- and bromine-substituted gem-dithiols depends on the properties of the medium, namely, in aprotic media aromatic dithiols form trithianorbornane derivatives while aliphatic dithiols form thiirane derivatives. In an aqueous medium (R = Me, Ph), water promoted elimination of hydrogen sulfide with the formation of corresponding thiones is more preferable. Thermolysis of aliphatic iodine-substituted gem-dithiols proceeds as bimolecular deiodination resulting in the formation of a new C-C bond.

A computational study of the reactions of thiiranes with ammonia and amines.

The relative rates of reaction of thiirane and thiirane derivatives with NH3, a series of secondary amines including aziridine, and trimethylamine were determined in the gas phase by means of B3LYP/6-31+G(d)//HF/6-31+G(d) computations and transition state theory. Convergence of the results was selectively tested using the 6-311++G(d,p) basis set. Comparison with MP2/6-31 + G(d)//MP2/6-31G(d) computations was made in model cases. These results are significant in that they supplement the only reported gas-phase experimental study of this type of reaction. The reaction rates of thiirane with secondary amines can best be rationalized by means of an interplay of steric and polarizability effects. While beta-halo substituents retard S(N)2 reactions in solution, both 2-fluorothiirane and its acyclic model react more than l0(6) times faster with NH3 than the unsubstituted compounds in the gas phase. 2-Fluorothiirane was calculated to react with NH3 at C2 by a factor of 0.142 with respect to thiirane itself; attack at C3 was found to be 3.42 x 10(6) times faster than the parent compound. 2-Methylthirane reacts with NH3 at 0. 230 the rate of thiirane with a 12.8-fold regioselectivity for C3. In the reaction of 2,2-dimethylthirane and NH3, this preference for C3 increases to a factor of 124. Ground-state destabilization of cis-2,3-dimethylthiirane is sufficient to account for its calculated rate acceleration with respect to the trans isomer.

ChemInform Abstract: 1,3‐Oxathiole and Thiirane Derivatives from the Reactions of Azibenzil and α‐Diazo Amides with Thiocarbonyl Compounds.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

1,3‐Oxathiole and Thiirane Derivatives from the Reactions of Azibenzil and α‐diazo amides with thiocarbonyl compounds

AbstractThe reactions of α‐diazo ketones 1a,b with 9H‐fluorene‐9‐thione (2f) in THF at room temperature yielded the symmetrical 1,3‐dithiolanes 7a,b, whereas 1b and 2,2,4,4‐tetramethylcyclobutane‐1,3‐dithione (2d) in THF at 60° led to a mixture of two stereoisomeric 1,3‐oxathiole derivatives cis‐ and trans‐9a (Scheme 2). With 2‐diazo‐1,2‐diphenylethanone (1c), thio ketones 2a–d as well as 1,3‐thiazole‐5(4H)‐thione 2g reacted to give 1,3‐oxathiole derivatives exclusively (Schemes 3 and 4). As the reactions with 1c were more sluggish than those with 1a,b, they were catalyzed either by the addition of LiClO4 or by Rh2(OAc)4. In the case of 2d in THF/LiClO4 at room temperature, a mixture of the monoadduct 4d and the stereoisomeric bis‐adducts cis‐ and trans‐9b was formed. Monoadduct 4d could be transformed to cis‐ and trans‐9b by treatment with 1c in the presence of Rh2(OAc)4 (Scheme 4). Xanthione (2e) and 1c in THF at room temperature reacted only when catalyzed with Rh2(OAc)4, and, in contrast to the previous reactions, the benzoyl‐substituted thiirane derivative 5a was the sole product (Scheme 4). Both types of reaction were observed with α‐diazo amides 1d,e (Schemes 5–7). It is worth mentioning that formation of 1,3‐oxathiole or thiirane is not only dependent on the type of the carbonyl compound 2 but also on the α‐diazo amide. In the case of 1d and thioxocyclobutanone 2c in THF at room temperature, the primary cycloadduct 12 was the main product. Heating the mixture to 60°, 1,3‐oxathiole 10d as well as the spirocyclic thiirane‐carboxamide 11b were formed. Thiirane‐carboxamides 11d–g were desulfurized with (Me2N)3P in THF at 60°, yielding the corresponding acrylamide derivatives (Scheme 7). All reactions are rationalized by a mechanism via initial formation of acyl‐substituted thiocarbonyl ylides which undergo either a 1,5‐dipolar electrocyclization to give 1,3‐oxathiole derivatives or a 1,3‐dipolar electrocyclization to yield thiiranes. Only in the case of the most reactive 9H‐fluorene‐9‐thione (2f) is the thiocarbonyl ylide trapped by a second molecule of 2f to give 1,3‐dithiolane derivatives by a 1,3‐dipolar cycloaddition.

Functional polythiiranes: 5. Side chain liquid crystalline polythiiranes

For the first time, a series of polythiiranes bearing in the side chain biphenyl and 4-alkoxybiphenyl mesogenic groups connected to the backbone with spacer groups of different lengths were prepared by anionic ring-opening polymerization of the corresponding thiirane derivatives. Unlike the corresponding polyoxiranes described in the literature, large methylene or oxyethylene spacers were needed in polythiiranes to observe liquid crystalline properties. But like the polyoxiranes, the polythiiranes exhibited mainly high ordered smectic A and E mesophases which were characterized by the usual techniques: d.s.c., polarized optical microscopy and X-ray diffraction.

Phthalimidosulphenyl chloride. Part 2. Synthesis of unusual thiirane derivatives.

Vinylthio phthalimides 1, synthesized by addition of phtalimidosulphenyl chloride to some alkynes, react with 2 equivalents of lithiumtriethylboron hydride to give vinylthio substituted thiiranes 3 with high degree of diasteroselectivity. The reaction of 1 with 1 equivalent of the same hydride affords divinyl disulphides 6 which resulted to be intermediates in the formation of thiiranes 3 since the reaction of 6 with 1 equivalent of lithiumtriethylboron hydride give the episulphides 3 in the same diastereoisomeric mixture. Mechanisms for these reactions are proposed.

Antioxidation properties of certain thiethane and thiirane derivatives

Antioxidation properties of certain thiethane and thiirane derivatives

Synthesis of thiirane derivatives of decahydroquinoline by the reaction of ?,?-epoxy alcohols with thiourea

The reaction of α,β-epoxy alcohols of the decahydroquinoline series with thiourea in water in the presence of sulfuric acid leads to 1-alkyl-, 1,2-dimethyl-, and 1,2,2-trimethyl-4-thiiranyl-trans-decahydro-4-quinolol carbamates, the structures of which were established by spectral methods.

Investigation of the anisotropy of the polarizability of certain thiirane derivatives

1. The molar Kerr constants were determined at infinite dilutions for a number of thioepihalohydrins and 4-cyanocyclohexene thioxide.