5373-55-7

Upstream product

• 936-61-8 Thiobenzoic acid O-ethyl ester 
• 106-49-0 p-toluidine 
• 103-82-2 phenylacetic acid 
• 98-88-4 benzoyl chloride 
• 99-99-0 1-methyl-4-nitrobenzene 
• 623-11-0 1-methyl-4-nitrosobenzene 
• 6725-34-4 thiobenzaldehyde 
• 611-73-4 Benzoylformic acid 
• 6313-36-6 benzyl thiosulphate 
• 100-51-6 benzyl alcohol 
• 3085-54-9 N-(4-methylphenyl)formamide 
• 6281-61-4 1-benzoyl-3-(4-methylphenyl)thiourea 
• 100-52-7 benzaldehyde 
• 98-07-7 Benzotrichlorid 

Downstream Products

• 103281-09-0 bis-(N-p-tolyl-benzimidoyl)-disulfane 
• 18263-23-5 Thiobenzoyl-p-toluidin-S-oxyd 
• 111273-17-7 4-(4-methylphenyl)-3-phenyl-1,2,4-oxadiazol-5(4H)-one 
• 2227-79-4 benzenecarbothioamide 
• 14016-00-3 6-methyl-2-phenylbenzoxazole 
• 69859-34-3 N-Methyl-thiobenzoyl-p-toluidin-S-oxid 
• 17572-14-4 N-<4-Methyl-phenyl>-N-methyl-thiobenzamid 
• 582-78-5 N-(4-methylphenyl)benzamide 
• 13432-42-3 N-<4-Methyl-phenyl>-S-methyl-isothiobenzamid 
• 31789-54-5 N²-p-Toluolsulfonyl-N¹-p-tolylbenzamidin 
• 36954-50-4 N-(4-methylphenyl)-benzamide oxime 
• 10205-58-0 6-methyl-2-phenyl-1,3-benzothiazole 

Relevant academic research and scientific papers

Solid Versus Solution Spin Crossover and the Importance of theFe-N - (X) Angle

A new family of mononuclear [FeII(Rdpt)2(NCE)2] complexes (E = S, Se, or BH3) is formed by 1:2 reaction of [FeII(pyridine)4(NCE)2] with the monotopic pyridyl triazole ligand 4-(4-methylphenyl)-3-(2-pyridinyl)-5-phenyl-4H-1,2,4-triazole (tolpyph). The three complexes are obtained as six different solvatomorphs: [FeII(tolpyph)2(NCS)2]·H2O (1·H2O), 1·1.5CH3OH·0.5H2O, [FeII(tolpyph)2(NCSe)2] (2), 2·1.5H2O, [FeII(tolpyph)2(NCBH3)2] (3), and 3·H2O. Single-crystal X-ray diffraction reveals that 1·1.5CH3OH·0.5H2O and 2 are high-spin (HS) at 100 K, while 3 is low-spin (LS) at 100 K and HS at 373 K. Compound 3 is the first structurally characterized example of an [FeII(Rdpt)2(NCE)2]-type complex with NCBH3 co-ligand: the crystal packing is dominated by aromatic stacking interactions. Solid-state magnetic measurements show that 1·H2O and 2·1.5H2O remain HS down to 50 K, whereas 3·H2O undergoes spin crossover (SCO) with a T1/2 of 309 K, slightly above room temperature. A literature survey of analogous trans-[FeII(Rdpt)2(NCX)2]-type complexes (53 distinct crystal structures) shows that for the complexes that are SCO active in the solid state the Fe-N - C(X) angle is usually close to straight, 162-178°, whereas it is usually lower, 142-159°, for the complexes that remain HS. UV-vis studies in CHCl3 solution show that in each case the use of a 6:1 ratio of tolpyph/Fe(II) is required to ensure the iron(II) is present in solution as [FeII(tolpyph)2(NCE)2]. Interestingly, using this ratio, all three compounds are SCO-active in CDCl3 solution-in dramatic contrast to the solid-state findings. Specifically, while compounds 1 and 2 are not SCO-active in the solid state (they remain HS), they undergo gradual SCO in CDCl3 solution, with T1/2 values of 290 and 310 K, respectively. In CDCl3 solution, compound 3 has a T1/2 value of 288 K, which is 21 K lower than in the solid state. These results highlight the differences between solid state (ligand field; crystal packing) and solution (ligand field; solvation) effects on SCO, with the latter studies revealing roomerature SCO for all three of these complexes.

A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson's reagent

After completing the thio-substitution with Lawesson's reagent, ethanol was found to be effective in the decomposition of the inherent stoichiometric six-membered-ring byproduct from the Lawesson's reagent to a highly polarized diethyl thiophosphonate. The treatment significantly simplified the following chromatography purification of the desired thioamide in a small scale preparation. As scaling up the preparation of two pincer-type thioamides, we have successfully developed a convenient process with ethylene glycol to replace ethanol during the workup, including a traditional phase separation, extraction, and recrystallization. The newly developed chromatography-free procedure did not generate P-containing aqueous waste, and only organic effluents were discharged. It is believed that the optimized procedure offers the great opportunity of applying the Lawesson's reagent for various thio-substitution reactions on a large scale.

Visible-Light Carbon Nitride-Catalyzed Aerobic Cyclization of Thiobenzanilides under Ambient Air Conditions

A metal-free heterogeneous photocatalysis has been developed for the synthesis of benzothiazoles via intramolecular C-H functionalization/C-S bond formation of thiobenzanilides by inexpensive graphitic carbon nitride (g-C3N4) under visible-light irradiation. This reaction provides access to a broad range of 2-substituted benzothiazoles in high yields under an air atmosphere at room temperature without addition of a strong base or organic oxidizing reagents. In addition, the catalyst was found to be stable and reusable after five reaction cycles.

Iron-Catalyzed Regioselective Synthesis of 2-Arylbenzoxazoles and 2-Arylbenzothiazoles via Alternative Reaction Pathways

A one-pot regioselective method for the preparation of 2-arylbenzoxazoles from N-arylbenzamides has been developed using iron(III)-catalyzed bromination of the aryl ring, followed by copper(I)-catalyzed O-cyclization with the benzamide side chain. In contrast, reaction of N-arylthiobenzamides with N-bromosuccinimide and iron triflimide led directly to the isolation of the corresponding 2-arylbenzothiazoles via intramolecular C–S bond formation. Mechanistic and control experiments suggest that in this case, bromination occurs at the sulfur atom, resulting in a reactive intermediate that can undergo electrophilic aromatic substitution and S-cyclization. The scope of both processes was explored yielding a range of structural analogues, including a pharmaceutically active compound for the treatment of Duchenne muscular dystrophy and an affinity agent of the amyloid-beta protein in Alzheimer's disease.

Mild and Chemoselective Thioacylation of Amines Enabled by the Nucleophilic Activation of Elemental Sulfur

A mild and chemoselective method for the thioacylation of amines using α-keto acids and elemental sulfur has been developed. The key to the success of this transformation is the nucleophilic activation of elemental sulfur by thiols such as 1-dodecanethiol

Extension of Azine-Triazole Synthesis to Azole-Triazoles Reduces Ligand Field, Leading to Spin Crossover in Tris-L Fe(II)

The first examples of azole-Triazole Rat ligands, bidentate L4NMeIm(3-(1-methyl-1H-imidazol-4-yl)-5-phenyl-4-(p-Tolyl)-4H-1,2,4-Triazole) and L4SIm (4-(5-phenyl-4-(p-Tolyl)-4H-1,2,4-Triazol-3-yl)thiazole), have been prepared, by extension of the general synthesis used to access many examples of azine-Triazoles. The tris-L FeII complexes of the azine-Triazoles are consistently low spin (LS). As intended, these new azole-Triazole ligands provide lower field strengths, resulting in high-spin (HS) [FeII(L4NMeIm)3](BF4)2 (1·4H2O) and spin crossover (SCO) active [FeII(L4SIm)3](BF4)2 (2·0.5H2O). Single-crystal structure determinations revealed that at 100 K 1·solvents is HS whereas 2·solvents is LS. Solid-state variable temperature magnetic studies of air-dried crystals showed that the methylimidazole-Triazole complex 1·4H2O remains HS while the thiazole-Triazole complex 2·0.5H2O undergoes a two-step gradual SCO (T1/2 approximately 275 and 350 K). Variable-Temperature Evans method NMR studies of 2, in five different solvents (CD3NO2, CD3CN, CD3COCD3, CD2Cl2, and CDCl3) gave T1/2 values in a relatively narrow range, 214-259 K. These T1/2 values did not correlate with the solvent polarity index P′ (R2 = 0.25) but did correlate with the solvent basicity parameter SB (R2 = 0.90). Variable-Temperature UV-vis studies on a golden yellow CH3CN solution of 2, with monitoring of the d-d transition at 530 nm (? = 39 L mol-1 cm-1 at 293 K) while the solution was heated from 253 to 303 K, showed that the high-spin fraction increased from 0.51 to 0.77. Cyclic voltammetry studies in CH3CN revealed a Fe(III)/Fe(II) redox process that was reversible for 1 and irreversible for 2, with significant tuning of the Epa value: The methylimidazole-Triazole complex 1 is significantly easier to oxidize (0.46 V) than the thiazole-Triazole complex 2 (0.68 V; both vs 0.01 M Ag/AgNO3).

Exogenous Photosensitizer-, Metal-, and Base-Free Visible-Light-Promoted C-H Thiolation via Reverse Hydrogen Atom Transfer

Visible-light-driven, intramolecular C(sp2)-H thiolation has been achieved without addition of a photosensitizer, metal catalyst, or base. This reaction induces the cyclization of thiobenzanilides to benzothiazoles. The substrate absorbs visible light, and its excited state undergoes a reverse hydrogen-atom transfer (RHAT) with 2,2,6,6-tetramethylpiperidine N-oxyl to form a sulfur radical. The addition of the sulfur radical to the benzene ring gives an aryl radical, which then rearomatizes to benzothiazole via RHAT.

Functionalization of activated methylene C-H bonds with nitroarenes and sulfur for the synthesis of thioamides

We report a method to obtain arylthioamides by the functionalization of sp3 C-H bonds in phenylacetic acids and benzyl alcohols. Reactions proceeded without the use of any solvents and were compatible with many functionalities and heterocycles. These conditions allow for a rapid synthesis of thioamides from simple, commercial substrates.

Transition metal-free α-Csp3-H oxidative sulfuration of benzyl thiosulfates with anilines to form N-aryl thioamides

A metal-free approach to N-aryl thioamides from Bunte salts and anilines in DMSO has been developed. This method tolerated a wide range of functional groups on the aromatic ring, providing an ideal way to N-aryl thioamides in good to excellent yields from cheap and easily available starting materials. A plausible mechanism was also proposed based on the X-ray single crystal diffraction, NMR and MS analyses of DMSO-concerning intermediates.

Iron-Promoted Three-Component 2-Substituted Benzothiazole Formation via Nitroarene ortho-C-H Sulfuration with Elemental Sulfur

A three-component procedure for the preparation of 2-substituted benzothiazoles from nitroarenes, alcohols, and sulfur powder is described. The reaction showed a good functional group tolerance to provide the heterocyclic products in moderate to good yields. The sequential assembly involving nitro reduction, C-N condensation, and C-S bond formation has been realized in one pot.