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Derivatives of N-acetyllactosamine carrying structurally diverse thioureido groups at galactose C3 were prepared from a C3'-azido N-acetyllactosamine derivative in a three-step reaction sequence involving azide reduction and isothiocyanate formation by thiophosgene treatment of the C3-amine, followed by reaction of the isothiocyanate with a panel of amines. Evaluation of the N-acetyllactosamine thioureas as inhibitors against galectins-1, 3, 7, 8N (N-terminal domain), and 9N (N-terminal domain) revealed thiourea-mediated affinity enhancements for galectins-1, 3, 7, and 9N. In particular, good inhibitors were discovered against galectin-7 and 9N (K-d 23 and 47 mu M, respectively, for a 3-pyridylinethylthiourea derivative), which represents more than an order of magnitude affinity enhancement over the parent natural N-acetyllactosamine. (c) 2005 Elsevier Ltd. All rights reserved. (Less)

A new synthetic protocol has been developed to provide entry into a series of novel tricyclic aryltriazole‐3‐thiones analogs. The classical reaction conditions of subjecting an arylhydrazide with thiophosgene to form the thioisocyanate intermediate and ultimately the corresponding aryltriazole‐3‐thione framework were not successful. However, using a combination of carbon disulfide and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) to form the thioisocyanate intermediate was found to produce the novel tricyclic aryltriazole‐3‐thiones (5, 8a–c) in good yield.

The vast majority of thiocarbonyl derivatives with two heteroatoms other than halogen or chalcogen contain two nitrogen functions and the main approach to their synthesis is based on addition reactions to isothiocyanates of amines. Also relevant are methods using carbon disulfide, thiophosgene, ureas, and thiocarbonyl transfer reagents. More restricted approaches include the use of thiocyanate salts and thiocarbamoyl or sulfur-transfer reagents. Analogously, derivatives with one nitrogen and one phosphorus function are usually prepared through addition of phosphines to isothiocyanates. A few examples are also described using halothioamides, thiophosphinoyldithioformates, and phosphonodithioformates. Finally, two syntheses of the almost unknown derivatives containing two phosphorus functions and two silicon functions are described.

A special xenon matrix detector has been used to study the production of S(1S) following controlled electron impact on thiophosgene (Cl2CS) targets over an electron energy range from threshold to 400 eV. Time-of-flight spectroscopy has been used to measure S(1S) fragment kinetic energies. Fragments with energies in excess of 1 eV have been observed. The absolute cross section for S(1S) production reaches a maximum of [1.05+/-0.35] x 10(-18) cm2 at approximately 125 eV impact energy. Two different fragmentation processes, involving triplet and singlet excited states of the parent Cl2CS molecule, have been identified.

Practical, facile and high-yielding one-pot syntheses of different O-unprotected glycopyranosyl thioureas and thioureido bolaamphiphiles (two-step synthesis) and of 2-amino-4,5-dihydro-(1,2-dideoxy-β-d-glucopyranoso)[1,2-d]oxazoles (three-step synthesis) from glycopyranosylamines are reported. The method involves the preparation of O-unprotected β-d-gluco (and d-galacto)pyranosyl isothiocyanates which are in equilibrium with the corresponding 1,2-cyclic thiocarbamates, coupling with amines to afford glycosyl thioureas and treatment with yellow mercury (II) oxide to give trans-fused bicyclic isoureas. A d-gluco trehazolin analogue is prepared in this way. In situ transformation of N,N-dialkyl, N′-glucopyranosyl thioureas into the corresponding ureas is also reported.

Twelve mercapturic acids derived from saturated and unsaturated aliphatic and aromatic isothiocyanates were synthesised, by adding isothiocyanate to a solution of N-acetyl-L-cysteine and sodium bicarbonate, in a typical yield of 77%. Isothiocyanates were synthesised first by adding the corresponding alkyl bromide to phthalimide potassium salt. The obtained N-alkyl-phthalimide was hydrazinolysed yielding the alkyl amine, which subsequently was reacted with thiophosgene yielding the isothiocyanate with an overall yield of 16%. Mercapturic acids in urine can serve as a biomarker of intake to determine the health promoting potential of isothiocyanates present in cruciferous vegetables. © 2003 Éditions scientifiques et médicales Elsevier SAS. All rights reserved.

Saturated fused systems such as imidazolidin[ 1,5-a]- and thiazolidin[3,4-a]perhydroquinoxalin-4-one as well as imidazolidin[1,5-a]piperazin-4-one derivatives were prepared by cyclocondensation reactions of appropriate perhydroquinoxalin-3-one and piperazin-3-one derivatives with diiodomethane and thiophosgene. An unusual ring contraction of perhydroquinoxalin-3-one derivatives to perhydrobenzimidazolidin-2-one derivatives by reaction with 1,2-dibromoethane was proved using crystal structure analysis with synchrotron and laboratory radiation sources.

5-Aryl-3-(4-hydroxyphenyl)-1,3,4-oxadiazole-2(3H)-thiones 3 were prepared by cyclocondensation of 1-(4-hydroxyphenyl)-2-aroylhydrazines with thiophosgene. All compounds exhibited antiproliferation activity in K562, IC(50) ranging from 24 to 94 micro M comparable efficacy with apigenin and genistein and showed more potent antiproliferation of K562/adr cells, highly expressing P-glycoprotein. Compounds 3g, 3e and 3a inhibited the function of P-glycoprotein with the alpha(0.5) equal to 10+/-3 micro M, 21+/-5 micro M and 34+/-7 micro M, respectively.

Asymmetric reduction of α,β-acetylenic ketones with B-3-pinanyl-9-borabicyclo[3.3.1]nonane: (R)-( + )-1-octyn-3-ol reactant: 35.3 g (0.285 mol) of 1-octyn-3-one product: 1-octyn-3-ol Keywords: addition, to CO; hydroboration; reduction, CO CHOH; assay methods, for thiophosgene; assay methods, of enantiomeric purity by NMR analysis with shift reagent; pinene, ( − )-α-, purification by distillation from LiAlH4; shift reagents, chiral; hydrogen peroxide

[937-64-4] C7H4Cl2OS (MW 207.08) InChI = 1S/C7H4Cl2OS/c8-5-1-3-6(4-2-5)10-7(9)11/h1-4H InChIKey = BQIABQCJXBELMT-UHFFFAOYSA-N (dehydrating agent;1 has been used in radical deoxygenation;2 serves as a building block in the synthesis of penems3 and heterocycles;4 used for introduction of the thiocarbonyl group5) Alternate Name: O-(4-chlorophenyl) carbonochloridothioate. Physical Data: bp 82 °C/0.8 mmHg;6 114–116 °C/0.8 mmHg.7 Form Supplied in: distillable liquid; commercially available. Preparative Method: from thiophosgene and p-chlorophenol in the presence of sodium hydroxide.2, 6 Handling, Storage, and Precautions: protect from moisture.

[81236-11-5] C16H35N3 (MW 269.54) InChI = 1S/C16H35N3/c1-11(2)17-16(18(12(3)4)13(5)6)19(14(7)8)15(9)10/h11-15H,1-10H3 InChIKey = YKRBTEJVESWMGV-UHFFFAOYSA-N (hindered amine base; used in oxidations of ketone hydrazones, and in eliminations of hydrogen iodide and p-toluenesulfonic acid) Preparative Method: the reagent is not commercially available, but is easily prepared in two steps. First, Thiophosgene is slowly added to Diisopropylamine to give N,N,N′,N′-tetraisopropylthiourea, as a pale yellow liquid, in 44% yield. A Vilsmeier salt is then formed from the reaction of tetraisopropylthiourea with Phosgene, and subsequently treated with isopropylamine to give 1,1,2,3,3-pentaisopropylguanidine (69% yield) as a liquid, bp 60 °C/0.01 mmHg (eq 1).1 The compound solidifies on storing at −20 °C under argon. (1) Handling, Storage, and Precautions: Use in a fume hood.

An expedient liquid-phase synthesis for construction of the diverse benzimidazole libraries is described. Nucleophilic aryl substitution of poly(ethylene glycol)-supported 4-fluoro-3-nitrobenzoic acid 3 with several primary amines under basic conditions, followed by Zn/NH(4)Cl mediated nitro group reduction, gave the PEG bound diamines 5. Subsequent cyclization of immobilized o-phenylenediamine 5 using thiocarbonyldiimidazole (TCD) or thiophosgene in dichloromethane furnished benzimidazole-2-thiones 6. Treatment of 6 with alkyl halides and benzylic halides in the presence of triethylamine provided 1-substituted-2-alkylthio-5-carbamoylbenzimidazoles on the support. The desired products 8 were severed from the PEG under mild conditions in high yield and high purity.

Polycarbonates and polythiocarbonates derived from diphenols containing Si or Ge, bis(4-hydroxyphenyl)-dimethyl-germane (I), bis(4-hydroxyphenyl)-diphenyl-germane (II), bis(4-hydroxy-phenyl)-dimethyl-silane (III), and bis(4-hydroxyphenyl)-diphenyl-silane (IV), and phosgene (a) or thiophosgene (b), respectively, were synthesized under phase transfer conditions using several phase transfer catalysts. The results were evaluated by the yields and ηinh values, showing that this technique was effective for the synthesis of this kind of polymers. The yields were low compared with those obtained with other diphenols, due probably to the use in this work of stoichiometric amounts of NaOH to avoid the decomposition of the diphenol, which hindered a salting out effect of the diphenolate to the organic phase. For part 24, see reference [14].

Scheme 2 Spiroorthocarbonates (SOCs) are one of the most important categories of monomers which polymerize without any shrinkage in volume. They are specially useful in the synthesis of materials such as precision materials, adhesives, and dental composites. There are few methods for the synthesis of SOCs. Sakai et. al. reported a novel synthesis of SOCs from the reaction of organotin compounds with carbon disulfide. This method is not recommended, Since it involves many steps and highly toxic unstable organotin compounds. Endo and Okawara also reported another synthetic method by treatment of tetraalkylorthocarbonate with various diols in the presence of TsOH as an acidic catalyst. The main disadvantage of this method comes from inevitable formation of symmetrical SOCs during the preparation of unsymmetrical analogs. Synthesis of SOCs is also achieved by using highly toxic thiophosgene which is not advised. The one pot treatment of dichlorodiphenoxymethane and various diols is useful only for the synthesis of symmetrical SOCs. Endo used dichlorodiphenoxymethane in the presence of p-toluenesulfonic acid monohydrate for the preparation of asymmetric SOCs. The long reaction times and relatively low yields are the disadvantages of this method. Therefore; an alternative method that can overcome these drawbacks and can be applied to the synthesis of symmetrical and unsymmetrical SOCs is desirable. Recently, molecular iodine has been the focus of attention in organic transformations as a mild, readily available and neutral Lewis acid. In continuation of our previous research on spiroorthocarbonates, in this paper, we wish to report on the use of this catalyst for the synthesis of symmetrical and unsymmetrical SOCs from 2,2-diphenoxy-1,3-dioxane and 1,3-diol under neutral conditions. 2,2-Diphenoxy-1,3-dioxanes (1a-b) used in this work were prepared according to literature. The reaction of 2,2-diphenoxy-1,3-dioxane (1a) with 1,3propanediol as a model reaction was performed in different aprotic solvents in the presence of I2. On the basis of the reaction times and yields, CH2Cl2 was selected as a most suitable solvent for the synthesis of SOCs. On the other hand, in order to get an insight into the optimum molar ratio of the catalyst, the model experiment was studied in four different molar ratios of the I2, and the results clearly demonstrate that 0.5% molar ratio of I2 related to 2,2-diphenoxy-1,3-dioxane is the optimal ratio. (Table 1) 2,2-Diphenoxy-1,3-dioxanes (1a-b) were reacted with various diols under neutral conditions in the presence of catalytic amount of molecular iodine (0.5 mol%) in CH2Cl2 to yield the corresponding SOCs (2a-j). (Scheme 1) The efficiency and validity of this method for the synthesis of SOCs (2a-j) can be deduced from the data in Table 2. Moreover, the prolongation of the reaction has no effect on the product distribution unlike the previous published method which uses protic acid catalyst. The proposed mechanism of the synthesis of SOCs catalyzed by molecular iodine for a typical synthesis (Entry 1) is presented in Scheme 2. In conclusion, we have developed a new modified, efficient and chemoselective method for the synthesis of symmetrical and unsymmetrical SOCs catalyzed by molecular iodine with good to high yields.

The trisaccharide allyl glycoside 36 and related disaccharide part structures have been prepared using the 2-trichloroacetamido-2-deoxy-α- d -galactopyranosyl trichloroacetimidate derivative 9 as glycosyl donor under promotion with TMSOTf or Sn(OTf)2, respectively, to produce the β-( 1 → 4) linkage to suitably protected glucosamine derivatives in fair yields. Fucosylation was effected employing the ethyl 1-thio glycosyl donor 20 in the presence of IDCP. Deprotection of the intermediates afforded the disaccharide allyl glycosides β- d -GalpNAc-( 1 → 4)-β- d -GlcpNAc 13, β- d -GalpNClAc-( 1 → 4)-β- d -GlcpNAc 14, α- l -Fucp-( 1 → 3)-β- d -GlcpNAc 24, α- l -Fucp-( 1 → 4)-β- d -GlcpNAc 31 and the branched trisaccharide allyl glycoside β- d -GalpNAc-( 1 → 4)[α- l -Fucp-( 1 → 3)]-β- d -GlcpNAc 36. The trisaccharide which corresponds to a structural motif occurring in N-glycoprotein glycans from human urokinase, human recombinant protein C, phospholipase A2 as well as O-glycans, was converted into a neoglycoprotein following introduction of a cysteamine-derived spacer group and subsequent activation with thiophosgene.

Pseudomonas sp. strain KC transforms carbon tetrachloride into carbon dioxide and nonvolatile products, without chloroform as an intermediate. To define the pathway for hydrolysis, nonvolatile products were analyzed. Condensation products containing the carbon atom of carbon tetrachloride as carbonyl and thioxo moieties were identified, indicating the intermediacy of phosgene and thiophosgene in the pathway.

International audience; The degradation of captan residues during the processing of apple to sterilised purée was investigated using laboratory small-scale processing (125 °C for 20 min and pH 4.0). [14C]-cyclohexene ring-labelled captan was completely degraded, mainly to tetrahydrophthalimide (96.5%). Other minor products such as tetrahydrophthalic acid (0.3) and tetrahydrophthalamic acid (0.2) were identified by HPLC and mass spectrometry. [14C]-trichloromethylthio-labelled captan was completely degraded essentially to [14C]CO2 (77%) accompanied by small amounts of [14C]CS2 (2%). Thiophosgene was not detectable. Approximately 11.5% of the radioactivity was non-extractable and was believed to result from the reaction of the trichloromethylthio moeity with endogenous compounds of the apple, e.g. protein. The results were compared with those obtained in buffer medium mimicking the same process.

Bis(pentamethylcyclopentadienyl) Ketone and Thioketone: Carbon Compounds with Performed Diels-Alder Geometry 1,2,3,4,5-Pentamethyl-1,3-cyclopentadien-5-carbonyl chloride (2) is formed in good yields by the reaction of pentamethylcyclopentadienyllithium (1) with phosgene. The corresponding carbothioyl chloride 3 is synthesized by treatment of 1 with thiophosgene. Both acyl chlorides are stable against air and moisture and difficult to attack in SN2-type reactions. Treatment of 2 and 3 with trimethyl(pentamethylcyclopentadienyl)stannane in the presence of boron trifluoride — ether leads to bis(1,2,3,4,5-pentamethyl-1,3-cyclopentadien-5-yl) ketone (5) and thioketone (6), respectively. Even at room temperature, 5 and 6 tend to intramolecular [4 + 2] cycloaddition reactions. X-ray crystal structure investigations of 2, 5, and 6 show the steric demand of the pentamethylcyclopentadienyl ligand and explain the untypical chemical behavior of 2 and the easy [2 + 4] cycloaddition reactions of 5 and 6.

A new radioiodination reagent, 3-iodophenylisothiocyanate (3-IPI) has been developed for coupling to monoclonal antibodies. The starting material, 3-tri-n-butylstannylphenylisothiocyanate was prepared via a reaction of hexabutylditin with 3-bromoaniline, followed by treatment with thiophosgene with an overall yield of 72%. The radioiodination of this tin precursor with Na[125I]I/iodogen in chloroform gave 3-[125I]IPI in 23-55% radiochemical yield and 81-99.6% radiochemical purity. Purification of the impure product by high pressure liquid chromatography increased the radiochemical purity of the product up to 99%. These results suggest that 3-IPI may be a useful ligand for radioiodination and coupling to a variety of monoclonal antibodies.

We propose and develop theoretically a general mechanism for the involvement of rotational motion into the nonradiative transitions that occur in an isolated polyatomic molecule. The treatment is based on the different rotational constants and different (asymmetric top-symmetric top) molecular structures in the two combining electronic states. We focus our attention on the T(1)--S(0) intersystem crossing (ISC) transition in thiophosgene and show how the rotational mechanism could lead to a considerable enhancement in the effective level density for the process. Inserting the rotational mechanism into our recently developed technique and algorithm for combined spin-orbit coupling+intramolecular vibrational redistribution analysis, we have carried out large-scale calculations that have led to a better understanding of the ISC (T(1)--S(0)) in thiophosgene.

Treatment of 1,2-di(pyrrol-1-yl)ethane 4 with oxalyl chloride gave a low yield of 5,6-dihydrodipyrrolo[1,2-d;2′,1′-g][1,4]diazepin-11-one 2, by an unexpected electrophilic substitution–decarbonylation process. The diazepinone 2 is unreactive to electrophiles, but can be deoxygenated to 5,6-dihydro-11H-dipyrrolo[1,2-d;2′,1′-g][1,4]diazepine 9 with lithium aluminium hydride. Reaction of 1,1-di(pyrrol-1-yl)methane 5 with triphosgene gives the related dipyrrolo[1,2-c;2′,1′-f]pyrimidin-10-one 3. NMR spectroscopic and X-ray crystal structure comparisons of 2 and 3 show that there is unexpectedly greater conjugation in the compound with the core seven-membered ring, 2, even though the molecule as a whole is less planar than 3. The corresponding reactions of 4 or 5 with thiophosgene did not give cyclisation products but the O-methyl thioesters 7 and 8 were obtained (89 and 27%, respectively).

3-Ethoxycarbonyl-2-isothiocyanatopyridine (2), prepared from 2-amino-3-ethoxycarbonylpyridine (1) by the thiophosgene method, was converted into thiouretanes 3 and 4, 1,4-disubstituted thiosemicarbazide 6, thioamide 8, and thioureas 15 and 18. The compounds 2 and 3 were converted into bicyclic pyrido[2,3-d]pyrimidines 5, 9, 10, 11, 12, 16, and 17, and tricyclic azolopyrido[2,3-d]pyrimidines 13 and 14.

We report the labeling of human gamma globulin with the 105Rh complex of a new pentadentate bifunctional ligand, 1,7-bis(2-hydroxybenzyl)-4-(p-aminobenzyl)diethylenetriamine. Complexes of this ligand with 105Rh were prepared by refluxing rhodium carrier spiked with 105Rh at pH9 in bicarbonate buffer. The complex was treated with an excess concentration of thiophosgene to prepare the isothiocyanate derivative which was extracted into CHCl3. The CHCl3 extract was dried and dissolved in DMF and reacted with a borate solution of human gamma globulin. Labeling yields were generally high and varied from 73% to 93%, depending upon the concentration of human gamma globulin and the isothiocyanate derivative of the complex used. The overall recovery of rhodium activity varied from 59% to 75% without taking into account activity lost due to decay. The conjugation reaction was complete by 4 h. From 0.4 to 8.5 atoms of Rh could be incorporated per molecule of protein by this method. The activated isothiocyanate complex did not show any degradation when stored at room temperature for up to 4 days and then used for conjugation.

To prepare the title compounds which show bent molecular shapes at the centers, a general synthetic route is developed. The successive treataent of 4,5-Vinylenedithio-1,3-dithiole-2-thione (5) with LDA, sulfur and thiophosgene gave the key intenediate of the dithione ( 6 ). The thiocarbonyl groups were oxidized to carbonyl groups by Hg(OAc) 2 . The coupling reaction of this diketone( 7 ) and 4,5-bis(aethylthio)-1,3-dithiole-2-thione ( 10 ) gave (MeS) 4 BTDT ( 1 , R 1 = R 2 =SCH 3 ) as the first example utilizing our synthetic strategy.

Unlike vicinal disulfenyl dichlorides whose carbon monosulfide diinsertion products readily cyclize with loss of thiophosgene, geminal disulfenyl dichlorides diinsert carbon monosulfide to form stable gem-bis(chlorodithioformates).

Crystal structure: monoclinic, P12 1 /c1, a=6.348, b=6.005, c=9.348A, β=98.71°, Z=2, T=115K, R=0.025

Oxazolidin-2-thiones can be prepared by the cyclization reaction of corresponding beta-amino alcohols with carbon disulfide or thiophosgene [1,2].[...]

A number of complementary synthetic approaches to the β-thiolactone intermediate 9 for elaboration to the novel 1,3-dioxo-1,2-dithiolane moiety 6 found in the antitumour antibiotic substance leinamycin 1 are described.Thus, deprotection of the benzylthio ether produced from 3-methylbut-2-enoic acid and toluene-α-thiol, leads to the mercapto acid 12 which on cyclisation produces the thiolactone 13. α-Methylation of the thiolactone 13, followed by α-oxygenation then gives rise to the substituted β-thiolactone 9. The β-thiolactone 9 is also produced when: (i) the sodium glycidate 17 is stirred with sodium sulfide leading to 18, followed by thiolactonisation; (ii) thioacetone is treated with the ketene derived from 2-acetoxypropanoyl chloride; and (iii) by irradiation of 3-methyl-2-trimethylsilyloxybut-2-ene 22 with thiophosgene leading to 23, followed by hydrolysis.The β-thiolactone 9 is then converted in three steps into the 1,3-dioxo-1,2-dithiolane 6 by: (i) ring opening to the thioic acid 15, using hydrogen sulfide–triethylamine; (ii) ring closure of 15 to 8 in the presence of aqueous ferric chloride; and finally (iii) oxidation using dimethyldioxirane.Treatment of the ethyl glycidate 19 with disodium disulfide in hot ethanol for 3 days provides the 1,2-dithiolane 8 directly, but in low yields (11–15%).When the aforementioned reaction sequences are translated to the glycidate 24, derived from 4-methylcyclohex-3-enone and α-chloropropanoic acid, the syntheses of the key intermediates 25, 27 and 26en route to the spiro-fused 1,3-dioxo-1,2-dithiolane 7 and leinamycin 1(see Scheme 1) were secured.

Colchiceinamide on reaction with phosgene and thiophosgene in the presence of triethylamine afforded tetracyclic compounds:benzo[9,10]heptaleno[4,3-d]oxazolones , -oxazolethiones . Treatment of the resulting tetracyclic oxazolethione with sodium hydroxide afforded tetracyclic thiazolone . All three tetracyclic compounds had very high negative specific rotations, but none of them inhibited tubulin polymerization in vitro.

Cyclization Reactions of β,γ-Unsaturated Derivatives of Carbonic Acid. VII. Synthesis of Unequivocal N-Acylated Thiazolidine-2-ones and Oxazolidine-2-ones A new synthetic route to N-acylated thiazolidine-2-ones and oxazolidine-2-ones is reported: The reaction of carboxylic acid chlorides with 2-alkoxy-2-thiazolines (1, 2) or -2-oxazolines (3) yields unequivocal N-acylated thiazolidine-2-ones (4–6) or oxazolidine-2-ones (7). Bifunctional acid chlorides, e.g. oxalyl chloride or thiophosgene yield compounds 11 and 12.

Durch Diels-Alder-Reaktion von 1-Phenyl-isopren (3) mit Thiophosgen (4) oder Cyandithioameisensaure-methylester (7) entstehen keine 4,6- sondern die 3,5-disubstituierten Thiopyrane 5 und 8. Die α-Pyrone 9 lassen sich mit Lawesson-Reagens zu den Pyran-2-thionen 10 schwefeln, mit NaSH in die Thiopyran-2-one 11 umlagern und mit Lawesson-Reagens erneut zu den Thiopyran-2-thionen 12 schwefeln. Alkylierung von 12 mit Phenacylbromid liefert die Pyrylium-bromide 13, die durch Erhitzen in Pyridin Schwefel eliminieren und mit Lawesson-Reagens in die 2H-Thiopyran-2-yliden-thioketone 2 ubergefuhrt werden konnen. 2a ist mit dem Hauptisomer der Umsetzung von 3-Methyl-5-phenyl-1,2-dithiolium-perchlorat (1) in Pyridin/Eisessig nach Lit. identisch. Independent Synthesis of 2H-Thiopyrane-2-ylidene-thioketones Diels-Alder reaction of 1-phenylisoprene (3) with thiophosgene (4) or methyl cyanodithioformate (7) leads to the 3,5-disubstituted thiopyranes 5 and 8, rather than to the 4,6-disubstituted compounds. The α-pyrones 9 react with Lawesson reagent to give the pyrane-2-thiones 10. Rearrangement of 10 with NaSH yields the thiopyrane-2-ones 11, which are once again sulfurised with Lawesson reagent to form 12. After alkylation of 12 with phenacyl bromide the pyrylium bromides 13 can be isolated. These lose sulfur on heating in pyridine and can be transformed to the 2H-thiopyrane-2-ylidene thioketones 2 with Lawesson reagent. Compound 2a is identical with the main isomer obtained by heating 3-methyl-5-phenyl-1,2-dithiolium perchlorate in pyridine/glacial acetic acid according to the literature.

Polythiocarbonates were synthesized from five different diphenols and thiophosgene under phase‐transfer catalysis conditions, with quaternary ammonium and phosphonium salts as catalysts and dichloromethane as solvent. The polythiocarbonates were characterized by IR, 1H NMR, and elemental analysis. Viscosity‐average molecular weights were estimated from inherent viscosity measurements. The influence of the catalysts and the structure of the diphenols both exert an important effect on the molecular weight. The hydrolysis of the polythiocarbonates was studied by observing the variation of ninh. The polymer undergoes a hydrolytic process in the organic phase, and this is influenced by the catalysts.

Selective laser excitation of a specific isotopic species to its lowest electronic singlet (S1) and triplet (T1) states respectively, then followed by a chemical reaction for isotope separation, is examined theoretically. It is found that the direct excitation to T1 state from ground state (S0) is an unique excitation channel for obtaining a controllable chemical reaction and for achieving a high isotope separation factor. This is due to the following important facts: (1) resonant energy transfer from a selectively excited triplet isotopic species to an unexcited species of the other isotope present in the mixture is missing (or is very small); (2) the lifetime of the T1 state is normally longer than that of the S1 state; (3) there is no intersystem crossing channel that exists for the deactivation of excited isotopic species from T1 state. Numerical calculation is performed for the chlorine isotope separation in a mixture of thiophosgene (0.5 torr) and diethoxyethylene (1.5 torr). The result indicates that the isotopic enrichment factor is at least 2.5 x 103 times larger for selective T1 excitation than that for S1 excitation.

An average hole-potential method (AHP) for studying molecular electronic structures and properties in excited states is suggested. The improved virtual orbitals (IVOs) prepared by this method are adapted to all possible transitions on the average. AHP calculations performed on the excited states of thiophosgene at the CNDO/2 level yield encouraging results.

Well resolved emission spectra have been recorded after dye laser excitation of low-lying vibronic levels in the B ( 1 A 1 ) state of Cl 2 CS. The effects of substrate pressure, added SF 6 and excitation wavelength on the spectra are reported. A Franck-Condon analysis suggests that the excited state CS bond length is 0.5 A longer than in the ground state.