Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions

Jordis, Ulrich; Bhattacharya, Kaberi; Boamah, Philip Y.; Lee, Ving J.

doi:10.3390/70200145

Open AccessArticle

Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions

by

Ulrich Jordis

^1,*,

Kaberi Bhattacharya

¹,

Philip Y. Boamah

¹ and

Ving J. Lee

²

¹

Institute of Organic Chemistry, VUT, A-1060 Vienna, Getreidemarkt 9, Austria

²

Microcide Pharmaceuticals Inc., 1335 Carvo Court, Los Altos, CA 94024, USA

^*

Author to whom correspondence should be addressed.

Molecules 2002, 7(2), 145-154; https://doi.org/10.3390/70200145

Submission received: 23 December 2001 / Accepted: 6 February 2002 / Published: 28 February 2002

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Abstract

:

Thieno[2,3-d]-1,2,3-thiadiazoles (1) react with carbon disulfide in a "Matryoshka-type" double compartment autoclave [1] to yield thieno[2,3-d]-1,3-dithiol-2-thiones (2). With BH₃/Me₂S the cyclic trithiocarbonate (2d) is cleaved and the product characterized after methylation as 4b. Compounds 7a and 7b are prepared via the thieno[2,3-d]-1,3-dithiolium salts (6) followed by NaBH₄-reduction.

Keywords:

1,3-dipolar cycloaddition; high pressure reaction

Introduction

Condensed 1,3-dithiole-2-thiones are valuable intermediates in the preparation of tetrathiafulvalene (TTF) - type organic metals [2]. Some of these compounds also exhibit antifungal activities [3]. Known methods of preparing thieno[2,3-d]-1,3-dithiole-2-thiones include either the annelation of the thiophene ring onto suitably substituted 1,3-dithiole-2-thiones [4,5] or the cyclization of thiophene thiole derivatives [6,7,8]. Thieno[2,3-d]-1,3-dithiole-2-thione has been synthesized by treatment of O-ethyl-S-(2-oxotetrahydrofuran-3-yl)dithiocarbonate with phosphorous sulfide or sulfur dehydrogenation of 4,5-dihydrothieno[2,3-d]-1,3-dithiole-2-thione [9a]. The formation of 2c via a thio-Claisen rearrangement has been described [9b]. The isomeric thieno[3,4-d]-1,3-dithiole-2-thione is formed as a side product by thermolysis of 4,6-dihydrothieno[3,4-d]-1,2,3-thiadiazole in the presence of an excess of carbon disulfide (6h, 170°C) [10].

Results and Discussion

In continuation of our previous work on the synthesis of 1,3-benzodithiole-2-thiones [11] we have investigated the reaction of thieno[2,3-d]-1,2,3-thiadiazoles [12] with carbon disulfide. The carbon disulfide thermolysis reactions were performed using a micro-scale, Teflon-autoclave within a 2L steel autoclave (Figure 1a and Figure 1b). By filling both the inner and outer autoclaves with the carbon disulfide solvent, one could reasonably expect that upon heating only a relatively small pressure difference would exist between the inside and outside of the Teflon autoclave, while the pressure within the steel autoclave was between 23 and 35 bar. Indeed, by using this procedure, reactions on a 140-840 mg scale could be performed routinely in this Matryoshka-autoclave, with the added advantage that contamination of the product by impurities (due to reaction of the autoclave with carbon disulfide) is avoided.

Figure 1a. Matryoshka Dolls and Matryoshka-Type Autoclave

Figure 1b. Autoclaves used in the experiments

The reaction temperature plays a critical role. The optimal temperature for the conversion of benzo-1,2,3-thiadiazole to 1,3-benzodithiole-2-thione was found to be 235±5°C [13] with a 67% yield of 2a formed, whereas below 220°C, 1a was mostly unreacted. Under similar reaction conditions the cyanide derivative 1f gave, in addition to the thieno[2,3-d]-1,3-dithiole-2-thione (2f), the 1,4,5,8-tetrathia-s-indacene (3f). The formation of the products 3d and 3f can be explained via head-to-tail dimerization of the 1,3-dipolar intermediate [14] (Scheme 1).

Scheme 1.

5-Phenylthieno[2,3-d]-1,3-dithiole was not detected upon reduction of 2d using the boron hydride/dimethyl sulfide complex. Instead, the ring-cleaved dithiole 4a was formed and characterized as the dimethylated compound 4b (Scheme 2).

Scheme 2.

This behavior is in contrast to the analogous conversion of 1,3-benzodithiole-2-thione to benzo-1,3-dithiole, which was produced routinely with yields of 88-92% in our laboratory [15]. On the other hand, 5-ethoxycarbonyl-6-methylthieno[2,3-d]dithiole-2-thione (2g) behaved analogously to benzo-1,3-dithiole-2-thione upon treatment with dimethyl sulfate followed by tetrafluoroboric acid. The crystalline salt 6 was then reduced to 7a using sodium borohydride in CH₃CN/THF. When ethanol was used for the reduction as described for similar reactions [16] a mixture of 7a and 7b was formed (Scheme 3):

Scheme 3.

2-Methylthio-thieno[2,3-d]-1,3-dithiolium salts (e.g. 6) could serve as starting materials for a host of synthetically useful reactions [17].

Conclusions

We have presented a facile route for the formation of thieno[2,3-d]-1,3-dithiol-2-thiones and developed a nested-type autoclave that allows to the use of Teflon autoclaves even under high pressure.

Experimental

General

Melting points were measured on a Kofler melting point apparatus. ¹H- and ¹³C-NMR-spectra were recorded on a Bruker AC-200 (200 MHz) pulse Fourier-transform NMR spectrometer using tetramethylsilane as an internal standard and, unless otherwise noted, CDCl₃ as solvent. Thin layer chromatography (TLC) was performed on Merck TLC aluminum sheets silica 60 F₂₅₄. Visualization was by UV light or spray reagents (molybdophosphoric acid or ninhydrin and heating). Column chromatography was performed using silica gel (Baker). MPLC (medium pressure liquid chromatography) was performed using a LC-8A pump (Shimadzu), a SPD-6AV UV-detector (Shimadzu) and Büchi preparative glass columns. All reactions were magnetically stirred under an argon atmosphere.

4-Cyano-3-methyl-but-3-enoic acid ethyl ester [18,19]. A mixture of ethyl acetoacetate (130.0 g, 1.0 mol), toluene (150 mL), cyanoacetic acid (90.0 g, 1.06 mol), ammonium acetate (16.0 g, 0.2 mol) and acetic acid (30 mL) was refluxed until azeotropic water removal ceased (8 h). Volatiles were removed in vacuo and the residue was partitioned between water and methylene chloride (400 mL). The organic phase was dried (Na₂SO₄), evaporated, and the crude product fractionated using a 30 cm Vigreux column to yield 106.5g (69.6%) of the product with b.p.₁₀ 110-118°C (Ref. 14a: b.p.₁₁ 114°C). According to ¹H-NMR, the eluted product fraction also contained isomeric 4-cyano-3-methyl-but-2-enoic acid ethyl ester. This product fraction was used for the preparation of 1a [20] via ethyl 2-amino-4-methyl-thiophene-5-carboxylate hydrochloride [21].

General procedure for the conversion of thieno[2,3-d]-1,2,3-thiadiazoles (1) to thieno[2,3-d]-1,3-dithiol-2-thiones (2) using the Matryoshka-autoclave. A 50-mL Teflon autoclave was charged with 1 (140-840 mg) and carbon sulfide (30 mL). This Teflon autoclave was inserted into a 2L steel autoclave and 100-200 mL carbon sulfide was added. The closed steel autoclave was heated for the time and temperature indicated in Table 1, developing a pressure of 35-40 bar. The reaction temperature was measured inside the steel autoclave using a thermocouple attached to a digital voltmeter as well as a strip chart recorder via an analog/digital interface. Following the prescribed reaction time, the cooled autoclaves were opened, the contents of the Teflon autoclave were evaporated to dryness with recovery of the carbon sulfide. The residue was purified by flash column chromatography using methylene chloride/petroleum ether (b.p. 40-60°C) 1:1 as eluant.

Table 1. Thermolysis of Thieno[2,3-d]-1,2,3-thiadiazoles

**Table 1.** Thermolysis of Thieno[2,3-d]-1,2,3-thiadiazoles
Run	Starting Mat.	R¹	R²	Scale (mg)	Temp. (°C)	Time (h)	Product (yield, %)	m.p. (°C)
1	1a	H	H	750	210-220	7	2a (37)	127-130 (toluene)
2	1a	H	H	240	230-240	8	2a (67)	127-130
3	1b	Cl	H	140	260-270	9	2b (10)^a	210-215 (LC)
4	1c	CH₃	H	140	235-245	9	2c (77)^b	–
5	1d	C₆H₅	H	150	240-267	9	3d (35)	223-224
6	1d	C₆H₅	H	150	210-220	7	2d (80)	175-177
7	1d	C₆H₅	H	840	210-230	6	2d (80)	175-177
8	1e	4-F-C₆H₄	H	140	230-240	9	2e (10)	156-158
9	1f	C₆H₅	CN	610	210-220	9	2f (18);	191-192
9	1f	C₆H₅	CN	610	210-220	9	3f (36)	302-305
10	1g	COOC₂H₅	CH₃	8550	207-218	7	2g (29)^c	169-170
11	1g	COOC₂H₅	CH₃	3500	225-232	6	2g (54)	169-170

Notes: ^aYield based on 64 mg starting material recovered; ^b Yield of crude product; ^cYield based on 3.4 g starting material recovered.

Table 2. Physical Properties of Compounds 2 and 3

**Table 2.** Physical Properties of Compounds 2 and 3
Product	Anal.	MS (m/z)	Remarks, NMR
2a	Calcd for C₅H₂S₄: C, 31.55; H, 1.06; Found: C, 31.70; H, 1.32.	190 (M⁺)	¹H-NMR: δ 6.85 (d, 1H, 4-H), 7.45 (d, 1H, H-6). ¹³C-NMR δ 119.9 (C-6), 130.8 (C-5), 132.5 (C-6a), 138.0 (C-3a), 215.2 (C=S).
2b	Calcd for C₅HClS₄: C, 26.72; H, 0.05. Found: C, 26.74; H, 0.30.	224 (M+, 100), 180, 150, 148, 113, 104, 69.	¹³C-NMR (CDCl₃/d₆-DMSO) δ 119.5 (C-6), 130.0, 136.1, 134.8 (C-3a, C-5, C-6a), 215.2 (C=S).
2c		204 (M⁺, 100), 169, 160, 140, 128, 113, 99, 85, 84, 71, 59, 57.	The crude product contained unreacted 1c and sulfur. A sample for MS was purified by flash-LC on silica using 7:3 petroleum ether/CH₂Cl₂ ¹H-NMR δ 2.58 (s, 3H, CH₃), 6.6 (s, 1H, C-H).
2d	Calcd for C₁₁H₆S₄: C, 49.59; H, 2.27. Found: C, 49.35; H, 2.18.	266 (M⁺, 100), 222, 190, 165, 146, 133, 121, 106, 102.
2e	Calcd for C₁₁H₅FS₄: C, 46.45; H, 1.77. Found: C, 46.48; H, 1.87.	284 (M+, 100), 240, 208, 164, 139, 120.	¹H-NMR δ 7.10 (s, 1H, H-6), 7.10-7.20 (m, 2H, arom.), 7.40-7.60 (m, 2H, arom.). ¹³C-NMR δ 115.5 (C-6), 116.2 (C-o ArF), 127.5 (C-m ArF), 128.0 and 132.0 (C-3a and C-6a), 138.5 (C-p ArF), 145.5 (C-5), 164.0 (C-ipso ArF), 214.5 (C=S).
2f	Calcd for C₁₂H₅NS₄: C, 49.46; H, 1.73; N, 4.81. Found: C, 49.22; H, 1.90; N, 4.47.	291 (M⁺, 100), 247, 227, 215, 171, 121.
2g	Calcd for C₉H₈O₂S₄: C, 39.11; H, 2.92; S, 46.40. Found: C, 38.98; H, 2.67; S, 47.33.	276 (M⁺, 100)	¹H-NMR δ 1.45 (t, 3H, CH₃CH₂), 2.57 (s, 3H, CH₃), 4.38 (q, 2H, OCH₂).
3d	Calcd for C₂₀H₁₂S₄: C, 63.12; H, 3.18. Found: C, 63.05; H, 3.31.	380 (M⁺, 100), 348, 303, 259, 190.	¹H-NMR δ 7.05 (s, 2H, 3H and 6-H), 7.25-7.50 (m, 10H, arom.). ¹³C-NMR δ 128.3, 128.5, 131.4, 131.5, 131.9, 132.0, 132.2, 133.6.
3f	Calcd for C₂₂H₁₀N₂S₄: C, 61.37; H, 2.34; N, 6.51. Found: C, 60.81; H, 2.09; N, 6.11.	430 (M⁺, 100), 398, 215, 121.

2,3-Bis-methylthio-5-phenyl-thiophene (4b). Borane-dimethylsulfide (200 mg, 26 mol) was added to a solution of 2d (160 mg, 6.0 mmol) in dry toluene (20 mL), and the reaction kept at 80-90°C until TLC showed complete consumption of the starting material (30 min). The cooled reaction mixture was hydrolyzed with dry MeOH and evaporated to dryness. The addition of MeOH and evaporation was repeated 3 times until the flame test for boron was negative. The crude product did not show any ¹H-NMR signals in the region of 4.5 ppm, indicative of the S-CH₂-S moiety of the expected dithioacetal 5. Alkylation using an excess of MeI and 20% N₂CO₃ gave, after extraction and Kugelrohr-distillation (0.2 mbar/110°C), 126 mg (72%) of 4b as a oil that solidified on standing, m.p. 36-68°C. ¹H-NMR δ 2.43 (s, 1H, SCH₃), 2.49 (s, 1H, SCH₃), 7.10 (s, 1H, H-4), 7.25-7.60 (m, 5H, arom.); MS m/z 252 (M⁺, 92), 237, 203, 173, 160, 145, 121, 102, 91, 77.

Ethyl 2-Methylthio-6-methylthieno[2,3-d]-1,3-dithiole-5-carboxylate (7a) and ethyl 2-ethoxy-2-methylthio-6-methylthieno[2,3-d]-1,3-dithiole-5-carboxylate (7b). Compound 1g [21](0.32 g, 1.16 mol) was stirred with freshly distilled dimethyl sulfate (4 mL) at 90-100°C under N₂ until it was dissolved (30 min.). To the cooled solution tetrafluoroboric acid (54%, 0.4 mL) was added, followed by ether (20 mL) to give 0.41g (93%) of crude 6. The yellow salt was dissolved in a 1:1 mixture of THF and MeCN (20 mL). NaBH₄ (0.2 g, 5.3 mol) was added, resulting in a colorless solution that was stirred for 1 h. The solvents were evaporated and the residue was partitioned between CH₂Cl₂/H₂O. The organic layer was dried (Na₂SO₄) and evaporated to yield 7a (0.25 g, 74%) as colorless crystals, m.p. 71-74°C (from petroleum ether/EtOAc). ¹H-NMR: δ 1.35 (3H, t, O-CH₂CH₃), 2.26 (s, 3H, C-CH₃), 2.47 (s, 3H, S-CH₃), 4.30 (q, 2H, O-CH₂), 6.50 (s, 1H, H-2). Anal. for C₁₀H₁₂O₂S₂: Calcd: C, 41.07; H, 4.14; S, 343.85. Found: C, 41.27; H, 3.86; S, 43.64. Using EtOH instead of THF/MeCN as the solvent [10] gave, after work-up and column chromatography on silica using 99:1 petroleum ether (b.p. 40-60°C)/t-BuOMe, a mixture of 7a and 7b. 7b eluted first and was characterized by its ¹H-NMR: δ 1.32 (3H, t, O-CH₂CH₃), 1.41 (3H, t, O-CH₂CH₃), 2.43 (s, 3H, C-CH₃), 2.47 (s, 3H, S.CH₃), 3.75 (q, 2H, O-CH₂), 4.30 (q, 2H, O-CH₂). The second fraction was identical with 7a prepared using THF/MeCN by ¹H-NMR and HPLC.

References and Notes

Matryoshkas (=Matriushka, Matrushka) nesting dolls were introduced at the end of the 19th century by the Russian artist Sergei Maliutin who painted a wooden doll as a peasant girl with a rooster. Inside of this hollow doll there were seven more dolls all painted differently (Figure 1a).
Bryce, M.R. Tetrathiafulfalene (TTF) and their selenium and tellurium analogs (TSF and TTeF): electron donors for organic metals. Aldrichimica Acta 1985, 18, 73–78. [Google Scholar]
See e.g. Chinothionat: Büchel, K.H. (Ed.) Pflanzenschutz und Schädlingsbekämpfungsmittel; Georg Thieme Verlag: Stuttgart, 1977.
Dölling, W.; Vogt, A.; Augustin, M. Synthesis of 1,3-dithiole-2-one derivatives, 2-ethylthio-1,3-dithiolium tetrafluoroborates and thieno[2,3-d]-1,3-dithiole-2-thiones. Z. Naturforsch. 1991, 46b, 133–138. [Google Scholar]
Dölling, W.; Augustin, M.; Ihrke, R. A simple method for the preparation of 6-amino-thieno[2,3-d]-1,3-dithiol-2-thiones. Synthesis 1987, 655–657. [Google Scholar]
Litvinov, V.P.; Dzhumaev, I.A. Condensed heteroaromatic 1,3-dithiole-2-thiones and their selenium analogs. Izv. Akad. Nauk SSSR, Ser. Khim. 1982, 717–718. [Google Scholar]
Litvinov, V.P.; Dzhumaev, I.A.; Zolotarev, B.M. Synthesis and mass-spectrometric study of condensed thiones-precursors of thiophene-type heterofulvalenes. Izv. Akad. Nauk SSSR, Ser. Khim. 1983, 2105–10. [Google Scholar]
Rasheed, K.; Warkentin, J.D. Thermal decomposition of dinitropyridyl and dinitrothienyl dithiocarbamates and t-butyl trithiocarbonates. J. Heterocycl. Chem. 1981, 18, 1581–1585. [Google Scholar]
Engler, E.M.; Patel, V.V.; Andersen, J.R.; Schumaker, R.R.; Fukushima, A.A. Organic Metals. Systematic molecular modifications of hexamethylene tetraheterofulvalene donors. J. Am. Chem. Soc. 1978, 100, 3769–3776. [Google Scholar] Kumar, E.V.K.S.; Singh, J.D.; Singh, H.B.; Das, K.; Verghese, B. Synthesis of Some Functionalised Isomeric Bis(ethylendithio)tetrahydrothiafulvalene (BEDT.TTF) and Dithiophenetetrahydrofulvalene (DTTTF)-p-Donors. Tetrahedron 1997, 53, 11627–11644. [Google Scholar]
Rovira, C.; Santalo, N.; Veciana, J. Bis(thiodimethylene)-tetrathiafulvalene (BTDM-TTF). A new π-electron donor with relevant oxidation properties. Tetrahedron Lett. 1989, 30, 7249–7252. [Google Scholar] Rovira, C.; Veciana, J.; Santalo, N.; Tarres, J.; Cirujeda, J.; Molins, E.; Llorca, J.; Espinosa, E. Synthesis of Several Isomeric Tetrathiafulvalene p-Electron Donors with Peripheral Sulfur Atoms. A Study of Their Radical Cations. J. Org. Chem. 1994, 59, 3307–3313. [Google Scholar]
Jordis, U.; Rudolf, M. Conversion of cyclic trithiocarbonates to thioacetals, including 1,3-dithiane, by reduction with diisobutylaluminium hydride (DIBAL). Phosph. Sulf. 1984, 19, 279–283. [Google Scholar]
Leading references for the preparation of thieno[2,3-d]-1,2,3-thiadiazoles: Stanetty, P.; Gorner, E.; Mihovilovic, M.D. An improved synthetic approach to thieno[2,3-d]-1,2,3-thiadiazole-carboxylates via diazotization of aminothiophene derivatives. J. Heterocycl. Chem. 1999, 36, 761–765. [Google Scholar] Stanetty, P.; Mihovilovic, M.D. A synthetic approach to methyl thieno[2,3-d]-[1,2,3]thiadiazolecarboxylates via diazotization. Monatsh. Chem. 1999, 130, 573–580. [Google Scholar] Stanetty, P.; Gorner, E.; Mihovilovic, M.D. An improved synthetic approach to thieno[2,3-d]-1,2,3-thiadiazolecarboxylates via diazotization of aminothiophene derivatives. J. Heterocycl. Chem. 1999, 36, 761–765. [Google Scholar]
U. Jordis, unpublished results.
Huisgen, R.; Weberndörfer, V. 1,3-Dipolare Additionen der Thioketocarbene. Experientia 1961, 17, 566. [Google Scholar]
Jordis, U. Hydride reduction of 1,3-benzodithiole-2-thiones and -selones. J. Chem. Res. (S) 1986, 432, J. Chem. Res. (M) 1986, 3401. [Google Scholar]
Bryce, M. R.; Coffin, M. A. J. Org. Chem. 1992, 57, 1696–1699.
Brown, C. A.; Miller, R. D.; Lindsay, C. M.; Smith, K. Generation of 2-lithio-(2-methylthio)-1,3-benzodithioles, new carbonyl carbanion equivalents, and their application to the synthesis of unsymmetrical hexaorthooxalates. Tetrahedron Lett. 1984, 25, 991–994. [Google Scholar]
Nakayama, J. The chemistry of 2-alkoxy-1,3-benzodithioles and 1,3-bonzodithiolium salts. Reactions and synthetic applications. Sulfur Rep. 1985, 4, 159–194. [Google Scholar]
Aldoshina, M.Z.; Atovmyan, L.O.; Goldenberg, L.M.; Krasochka, O.N.; Lubovskaya, R.N.; Lubovskii, R.B.; Merzhanov, V.A.; Khidekel, M.L. A new series of radical-cation salts based on asymmetrical ethylendithiodimethyltetrathiafulvalene (EDTDM-TTF). J. Chem. Soc., Chem. Commun. 1985, 1658–1661. [Google Scholar]
Simchen, G. Eine neue allgemeine Heterocyclensynthese durch Alkylierung von Nitril-Halogenwasserstoffaddukten. Habilitationsschrift Universität Stuttgart. 1968. [Google Scholar]
Hennecke, H. DBP 1023464 (1958); [Chem. Abstr. 1960, 54, 5704e].
Gewald, K.; Hain, U.; Madlenscha, M. 2,3-Heterocondensed thiophenes from substituted 2-aminothiophen-3-thiole. J. prakt. Chem. 1988, 330, 866–872. [Google Scholar]
Gewald, K.; Hentschel, M.; Heikel, R. 2-Amino-thieno[2,3-d]thiazoles und 3-amino-thieno[2,3-c]isothiazoles. J. prakt. Chem. 1973, 315, 539–548. [Google Scholar]

Sample Availability: Compounds 2c-d, 3d and 4b are available from MDPI.

Appendix: Information on Matryoshkas

Many links to information about Matryoshkas can be found in the Web by using the 3 most common transliterations in search engines.

Figure 2. Examples of matryoshkas*:

* I thank my friends Victoria & Peter H. for allowing me to take photographs of their impressive collection of matryoshkas.

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Jordis, U.; Bhattacharya, K.; Boamah, P.Y.; Lee, V.J. Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions. Molecules 2002, 7, 145-154. https://doi.org/10.3390/70200145

AMA Style

Jordis U, Bhattacharya K, Boamah PY, Lee VJ. Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions. Molecules. 2002; 7(2):145-154. https://doi.org/10.3390/70200145

Chicago/Turabian Style

Jordis, Ulrich, Kaberi Bhattacharya, Philip Y. Boamah, and Ving J. Lee. 2002. "Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions" Molecules 7, no. 2: 145-154. https://doi.org/10.3390/70200145

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Synthesis of Thieno[2,3-d]-1,3-dithiol-2-thiones from Thieno[2,3-d]-1,2,3-thiadiazoles: Matryoshka-type autoclave for high-temperature, high-pressure thermolysis microscale reactions

Abstract

Introduction

Results and Discussion

Conclusions

Experimental

General

References and Notes

Appendix: Information on Matryoshkas

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