505-23-7

Usage

Uses

Used in Organic Synthesis:
1,3-Dithiane is used as a reagent in umpolung reactions, such as the Corey-Seebach reaction, for the deoxygenation of sulfoxides to their corresponding sulfides. This reaction allows for the formation of new carbon-carbon bonds and the synthesis of complex organic molecules.
Used as a Protecting Group:
1,3-Dithiane is used as a protecting group for carbonyl compounds in organic synthesis. It can be easily introduced and removed, allowing chemists to control the reactivity of specific functional groups during the synthesis process.
Used as a Labeled Synthon:
1,3-Dithiane serves as a useful labeled synthon, providing a convenient and efficient method for the synthesis of various organic compounds.
Used in the Preparation of 2-Ethyl-[1,3]dithiane:
1,3-Dithiane is used in the preparation of 2-ethyl-[1,3]dithiane, which is an important intermediate in the synthesis of pharmaceuticals and other organic compounds.

Reactions

1,3-dithiane has 2 weakly acidic protons that can be removed and alkylation of the carbon is possible. Once alkylated, the 1,3-dithiane becomes a “protected” carbonyl as it can be hydrolyzed to the corresponding carbonyl structure. Alternatively, the 1,3-dithiane moiety may also be introduced by thioacetalisation of a carbonyl group, either using acid or Lewis acid catalysis, 12 or of a 1,1-dihalide (using transition metal catalysis).

Synthesis Reference(s)

Tetrahedron Letters, 29, p. 4477, 1988 DOI: 10.1016/S0040-4039(00)80527-4

Purification Methods

Crystallise the 1,3-dithiane from 1.5 times its weight of MeOH at 0o, and sublime it at 40-50o/0.1mm. [Groel & Seebach Synthesis 357 1977, Beilstein 19/1 V 13.]

InChI:InChI=1/C4H8S2/c1-2-5-4-6-3-1/h1-4H2

Upstream product

• 109-80-8 1.3-propanedithiol 
• 64211-37-6 1,3-dithiacyclohexan-5-one 
• 109-64-8 1,3-dibromo-propane 
• 36236-76-7 4-(bromomethyl)-2,2-dimethyl-1,3-dioxolane 
• 36049-90-8 2-lithio-1,3-dithiane 
• 50-00-0 formaldehyd 
• 75-11-6 diiodomethane 
• 109-87-5 Dimethoxymethane 
• 462-95-3 formaldehyde diethyl acetal 
• 14371-10-9 (E)-3-phenylpropenal 
• 13411-42-2 2-(trimethylsilyl)-1,3-dithiane 
• 1748-15-8 1,3-dithiane-2-thione 
• 120-57-0 piperonal 
• 124-13-0 Octanal 

Downstream Products

• 26413-18-3 1,3-dithiane 1,1,3,3-tetraoxide 
• 624-08-8 9-heptadecanol 
• 56080-57-0 1,1-diphenyl-6,10-dithia-1-sila-spiro[4.5]decane 
• 56080-59-2 7-methyl-7-phenyl-1,5-dithia-7-sila-spiro[5.5]undecane 
• 56080-58-1 7,7-diphenyl-1,5-dithia-7-sila-spiro[5.5]undecane 
• 56080-61-6 7,7-diphenyl-1,5-dithia-7-sila-spiro[5.6]dodecane 
• 14947-48-9 2-(2'-hydroxyethyl)-1,3-dithiane 
• 53178-47-5 2-(2-hydroxy-2-phenylethyl)-1,3-dithiane 
• 13411-42-2 2-(trimethylsilyl)-1,3-dithiane 
• 81793-31-9 1-[1,3]Dithian-2-yl-5,5-dimethyl-cyclohex-2-enol 
• 142671-75-8 2-(1,3-dithian-2-yl)-2-(α-hydroxybenzyl)-1-methyl-quinolin-4(1H)-one 
• 142671-82-7 2-(1,3-dithian-2-yl)-2-(α-hydroxybenzylidene)-1-methyl-2,3-dihydroquinolin-4(1H)-one 
• 5425-44-5 2-Phenyl-[1,3]dithiane 
• 36998-40-0 2,2-diphenylmethylene-1,3-dithiane 

Relevant academic research and scientific papers

Kinetics of the [2+ + 4]-cycloaddition reactions of 1,3-dithian-2-ylium ions with 1,3-dienes

The kinetics of the [2+ + 4] cycloadditions of 1,3-dithian-2-yhum ions (1) with 1,3-dienes was investigated photometrically in dichloromethane. The second-order rate constants determined for the reactions of 1 with 2,3-dimethyl-1,3-butadiene (2a) and isoprene (2b) were identical to those calculated for the first step of a stepwise cycloaddition pathway by the correlation Ig k = s (E + N). Though a concerted cycloaddition pathway is not excluded by this finding, it is obvious that the transition states of these reactions are not noticeably stabilized by the simultaneous formation of two new σ bonds.

CARBON-SULPHUR BOND FORMATION CATALYSED BY BIS(DIPHENYLPHOSPHINO)-METHANE COMPLEXES OF PLATINUM(II)

Thiols react with alkylhalides in the presence of sodium carbonate and a catalytic quantity of (dppm)PtCl2 to give thioethers.Of especial interest is the succesful application to thioacetal formation using 1,1-dihalides which, does not require the use of strong bases or the intermediacy of thiolate anions.

Electrophilic Chlorine from Chlorosulfonium Salts: A Highly Chemoselective Reduction of Sulfoxides

Herein, we describe a selective late-stage deoxygenation of sulfoxides based on a novel application of chlorosulfonium salts and demonstrate a new process using these species generated in situ from sulfoxides as the source of electrophilic chlorine. The use of highly nucleophilic 1,3,5-trimethoxybenzene (TMB) as the reducing agent is described for the first time and applied in the deoxygenation of simple and functionalized sulfoxides. The method is easy to handle, economic, suitable for gram-scale operations, and readily applied for poly-functionalized molecules, as demonstrated with more than 45 examples, including commercial medicines and analogues. We also report the results of competition experiments that define the more reactive sulfoxide and we present a mechanistic proposal based on substrate and product observations.

Selective Conversion of Carbon Dioxide to Formaldehyde via a Bis(silyl)acetal: Incorporation of Isotopically Labeled C1 Moieties Derived from Carbon Dioxide into Organic Molecules

The conversion of carbon dioxide to formaldehyde is a transformation that is of considerable significance in view of the fact that formaldehyde is a widely used chemical, but this conversion is challenging because CO2 is resistant to chemical transformations. Therefore, we report here that formaldehyde can be readily obtained from CO2 at room temperature via the bis(silyl)acetal, H2C(OSiPh3)2. Specifically, formaldehyde is released from H2C(OSiPh3)2 upon treatment with CsF at room temperature. H2C(OSiPh3)2 thus serves as a formaldehyde surrogate and provides a means to incorporate CHx (x = 1 or 2) moieties into organic molecules. Isotopologues of H2C(OSiPh3)2 may also be synthesized, thereby providing a convenient means to use CO2 as a source of isotopic labels in organic molecules.

Reduction of CO2 into Methylene Coupled with the Formation of C-S Bonds under NaBH4/I2 System

A selective four-electron reduction of CO2 with thiophenol using NaBH4 as a reductant is described to access dithioacetals. This reaction provides a novel synthetic method for the highly selective conversion of CO2 into methylene, and a new access to molecular structures via formation of C-S bonds using CO2 as the C1 source.

Pot-economy autooxidative condensation of 2-Aryl-2-lithio-1,3-dithianes

The autoxidative condensation of 2-aryl-2-lithio-1,3-dithianes is here reported. Treatment of 2-aryl-1,3-dithianes with n-BuLi in the absence of any electrophile leads to condensation of three molecules of 1,3-dithianes and formation of highly functionalized α-thioether ketones orthothioesters in 51-89% yields upon air exposure. The method was further expanded to benzaldehyde dithioacetals, affording corresponding orthothioesters and α-thioether ketones in 48-97% yields. The experimental results combined with density functional theory studies support a mechanism triggered by the autoxidation of 2-aryl-2-lithio-1,3-dithianes to yield a highly reactive thioester that undergoes condensation with two other molecules of 2-aryl-2-lithio-1,3-dithiane.

Synthesis of 8-methylnonane-1,6,7-trien-4-one and related allenes as potentially useful synthetic precursors

The allenic ketone 8-methylnonane-1,6,7-trien-4-one and related allenes have been synthesized from simple commercially available materials. Since allenes analogous to 8-methylnonane-1,6,7-trien-4-one have previously been transformed to substituted bicyclo[3.3.0]octanones via corresponding bicyclo[3.2.0]heptanones, it is anticipated that the present allenic ketone may also undergo similar transformations. Substituted bicyclo[3.3.0]octanones are known synthetic precursors of tricyclic sesquiterpenes. Thus, 8-methylnonane-1,6,7- trien-4-one presents itself as a possible precursor for the synthesis of tricyclopentanoid ring system present in sesquiterpenes such as hirsutene and Δ9(12)-capnellene.

Molybdenum pentachloride (MoCl5) or molybdenum dichloride dioxide (MoO2Cl2): advanced catalysts for thioacetalization of heterocyclic, aromatic and aliphatic compounds

A new, convenient and mild method for thioacetalization of heterocyclic, aromatic and aliphatic compounds catalyzed by MoCl5 or MoO2Cl2 is described. This novel method is important for the synthesis of the difficult to prepare heterocyclic thioacetals such as the pterin thioacetals and it offers significant advantages such as high conversion, short reaction times and simplicity in operation.

Oxalic acid catalyzed reaction between dithioacetals and acetals. A simple and eco-friendly method for a conversion of a dithioacetal to a carbonyl compound

Oxalic acid catalyzes a reaction between dithioacetals and acetals. This reaction is useful in a new and eco-friendly method to convert dithioacetals to carbonyl compounds.

Externally sensitized mesolytic fragmentations in dithiane-ketone adducts

The apparent activation enthalpies, ΔH≠, for externally sensitized mesolytic fragmentations in benzophenone-dithiane adducts were obtained in variable temperature photolyses and compared with DFT activation barriers calculated for β-scission in the corresponding oxygen-centered radicals. The results of these experimental and theoretical studies further support the mechanism in which deprotonation of the hydroxy-group, in the transient cation radical, is coupled with intramolecular electron transfer furnishing the O-centered radical, which subsequently fragments. The quantum yields of fragmentation increase for higher alkyl substituted dithiane adducts.