3844-31-3

Upstream product

• 520-72-9 3-hydroxybenzothiophene 
• 53633-39-9 2-<4-(dimethylamino)phenyl>-imino benzo-thiophen-3-(2H)-one 
• 574-69-6 4-(4-hydroxy-[1]naphthylazo)-benzenesulfonic acid 
• 130-03-0 thioindoxyl 
• 64-19-7 acetic acid 
• 88690-93-1 2-(phenylimino)benzo-thiophen-3-(2H)-one 
• 191031-07-9 3-hydroxy-benzo[b]thiophene-2-carboxylic acid 
• 141-97-9 ethyl acetoacetate 
• 147-93-3 Thiosalicylic acid 
• 3528-17-4 2,3-dihydro-4H-[1]benzothiopyran-4-one 
• 28035-02-1 2,2-dimethylthiochroman-4-one 
• 57314-29-1 3-bromothiochroman-4-one S-oxide 
• 491-39-4 thiochromen-4-one 
• 68847-94-9 3-bromo-4H-thiochromen-4-one 

Downstream Products

• 520-72-9 3-hydroxybenzothiophene 
• 493-57-2 benzo-[b]thiophene-2,3-dione 
• 241-13-4 Bis(benzo<4,5>thieno)<3,2-b:2',3'-d>thiophen 
• 1083-56-3 1,4-diphenylbutane 
• 65-85-0 benzoic acid 
• 495-71-6 phenacylacetophenone 

Relevant academic research and scientific papers

Effect of the Phase Transition of Smectic Liquid-Crystalline Solvent on the Thermal Isomerization of 5,5'-Dialkylthioindigo Compounds

The rates and the activation parameters for the thermal cis-to-trans isomerization of 5,5'-dialkylthioindigo dyes embedded in a smectic mesophase of butyl stearate were affected by the transition of the liquid-crystalline to the isotropic phase, depending upon the alkyl length.

Reversible photochemical isomerization of N, N ′-Di(t -butoxycarbonyl)indigos

We report on the photophysics of N,N′-di(t-butoxycarbonyl)indigos (tBOC indigos), finding that reversible photochemical trans-cis and cis-trans isomerization reactions proceed with high quantum yields (0.10-0.46). Absorption of wavelengths in the 500-600 nm region induces trans-cis isomerism, while blue light leads to the reverse cis-trans process. Like their parent indigos, trans-BOC indigos have low fluorescence yields (～1 × 10-3), while the cis isomers have no measurable emission. These compounds are the first examples of photoisomerizable indigoid dyes in which photochemical isomerism effectively outcompetes radiative decay processes. Though indigo dyes typically have poor solubility in organic solvents, tBOC indigos can be dissolved at concentrations up to 8 w% in common organic solvents like acetone. Furthermore, unlike other photoisomerizable indigoids, tBOC indigos are not sensitive to quenching by proton and electron donors. These features, combined with high quantum yields of reversible photoisomerism induced by relatively low-energy photons (～2 eV), make tBOC indigo derivatives potentially interesting for photochromic applications, such as photomechanically actuated materials.

Thioindigo precursor: Control of polymorph of thioindigo

The precursor was converted to thioindigo with P21/c structure by heating. 2,2′-Bi[-3(2H)-thiophenon]ylidene with two bicyclo[2.2.2]-octadiene moieties was quantitatively converted to thioindigo by the retro-Diels-Alder reaction. The thioindigo solid obtained from the precursor had the P21/c structure which was different from the commercial thioindigo samples (P21/n).

EINE NEUE SYNTHESEVARIANTE ZUR DARSTELLUNG VON THIOINDIGOIDEN

Dithiocarboxylates prepared in situ by thiolation of 2-chloroacetophenones react at higher temperatures by intramolecular substitution of chlorine followed by C=C bond formation under loss of sulfur to provide thioindigoides in good yields.Diethoxy-disulfan is employed as sulfur transfer reagent in this thiolation process. - Key words: Thioindigo, thiolation, sulfur transfer reagents, diethoxy-disulfan, 2-chloro-acetophenones, desulfuration.

Electroreduction of Organic Compounds, 19. Formation of Benzoanellated Sulfur Heterocycles by Intramolecular Cathodic Cyclization of Dithiocarboxylic Esters

Cathodic reduction of aryl (3) and benzyl (5) dithiopivaloates and related dithioesters with leaving groups at the benzene ring or a side chain yield the sulfur heterocycles 23, 30 - 32, and 34 depending on the nature of the starting material and the reaction conditions.In the case of the α-oxo-dithioester 22, thioindigo (44) is formed. - The corresponding thioamides 14, 16, and 18 show a strong tendency to reductive dehalogenation but the S,N-heterocycles 38 and 39 are also formed in minor amounts. - The formation of the rearranged products 29 - 32, and 34 isdiscussed in terms of C,S-splitting in the primarily formed radical anion and subsequent C,C-coupling of the fragments and follow-up reactions.Key Words: Dithiopivaloates, S-aryl, S-benzyl / Electroreduction

Synthesis of 2-(Aminomethylene)-2H,3H-1-benzothiophene-3-one from 3-Bromo-4H-1-benzothiopyran-4-one as a New Donor-acceptor Chromophore

2-(Amino-substituted methylene)-2H,3H-1-benzothiophene-3-ones were prepared by ring contraction of 3-bromo-4H-1-benzothiopyran-4-one with amines, as a new donor-acceptor chromophore.The structure of 2-(N,N-dimethylaminomethylene) derivative was determined by X-ray crystallographic analysis.

USE OF NITROBENZENE FOR PREVENTING THE CATALYTIC ACTION OF TRACE IMPURITIES ARISING DURING PHOTOISOMERIZATION OF THIOINDIGO IN BENZENE SOLUTIONS.

The persistence of an image on a photochromic material depends on the thermal stability of the photoinduced form. Identification of the factors tending to lower the rate constant of spontaneous transition of the thermodynamically unstable into the stable form is examined. It is shown that (1) Nitrobenzene added before irradiation in amounts 1-10% to a solution of thioindigo in benzene does not inhibit photochemical formation of trace impurities; (2) addition of an equal amount (by volume) of nitrobenzene immediately after irradiation of a solution in benzene lowers the rate constant by a factor of 10-20; the constant becomes lower by a factor of 3 than in a chromatographically purified benzene solution of the Z isomer but remains 13 times as high as in nitrobenzene itself, and approximately equal to the rate constant in nitrobenzene containing 10** minus **3 mole multiplied by (times) liter** minus **1 of such active catalysts of Z yields E isomerization as p-toluenesulfonic acid or dibutylamine.

THIOINDIGO ON SILICA GEL AND ON ALUMINUM OXIDE: UNEXPECTED DIFFERENCES IN THE DIRECTION OF PHOTOISOMERIZATION OF ADSORBED MOLECULES.

The purpose of this work was to study the behavior of the photochromic dye thioindigo in the course of adsorption and in the adsorbed state on silica gel, and to compare the results with published data on the behavior of thioindigo on aluminum oxide. The explanation offered for the ability of thioindigo, adsorbed in the form of 0. 1 M solution on aluminum oxide, to undergo E yields Z (but not Z yields E) photochemical isomerization is that on aluminum oxide both halves of the Z-isomer molecule are adsorbed equally strongly, whereas in the case of the E isomer one half of the molecule 'hovers' over the surface, retaining the torsional degree of freedom. If we accept this interpretation, it follows from the fact that photochemical Z yields E (but not E yields Z) isomerization occurs on silica gel, that the active sites on aluminum oxide and on silica gel differ strongly in their geometry, favoring stabilization of the configuration of nonplanar molecules in the first case and of more planar molecules in the second.

Thiopyranothiopyran Chemistry. 5. Synthesis of Dibenzothiopyranothiopyran-6,12-dione (Thioepindolidione)

Tne novel thioepindolidione, a derivative of a thiopyranothiopyran, was synthesized from thiochroman-4-one.The absorption and fluorescence characteristics of thioepindolidione are compared with those of thioindigo and epindolidione.

Ring Transformation of 3-Hydroxy-1,2,5- and -1,2,4-thiadiazoles and -isothiazoles into Isothiazole , Thiazole and Thiophene Derivatives

Ring transformation of 3-hydroxy-1,2,5-thiadiazole (1), 3-hydroxy-1,2,4-thiadiazole (14), and 3-hydroxyisothiazole (18) by the reaction with acetic anhydride in the presence of DBU afforded isothiazoles 2-5 and 13, thiazoles 15 and 16 and thiophenes 21-25, respectively.The reaction of 1 with propionic anhydride gave isothiazole 13.The formation pathway of the products is mentioned.