The reaction of tert-butyl- or THP-protected mandelic thioacid (7a and 7b) with N,N,2,2-tetramethyl-2H-azirin-3-amine (2a) gave the dipeptide analogues tBu- and THP-Mns-Aibψ[CS]NMe 2 (8a and 8b, resp.) with a C-terminal thioamide group. Treatment of 8a with HCl gas in toluene led to 2-(1-rert-butoxybenzyl)-4,4-dimethyl-1,3-thiazole-5(4H)-one (9), which reacted with dimethylamine via ring opening to give tBu-Mnsψ[CSNH]Aib-NMe2 (lla), an isomer of8a with the thioamide group within the chain, i.e., the product of a sulfur migration. In the case of 8b, selective deprotection of the THP-hydroxy group was achieved by treatment with pyridinium p-toluenesulfonate (PPTS) in ethanol. Cyclization of the resulting Mns-Aibψ[CS]NMe 2 (13) yielded the 2-thioxomorpholin-5-one 10. In a similar manner, Boc-Val-SH (14) reacted with azirine 2b to give Boc-Val-Aibψ[CS]N(Me)Ph (15a), which was transformed to Fmoc-Val-Aibψ[CS]N(Me)Ph (15b) and further to Fmoc-Valψ[CSNH]Aib-N(Me)Ph (16) by treatment with ZnCl 2 in acetic acid. Coupling of two of these molecules via the 1,3-thiazol-5(4H)-one 17 yielded the endodithiopeptide Fmoc-Valψ[CSNH]Aib-Valψ[CSNH]Aib-N(Me)Ph (19).
{"title":"Synthesis of Endothiopeptides by Using the 'Azirine/Oxazolone Method'","authors":"A. Bärtsch, B. Bischof, H. Heimgartner","doi":"10.5167/UZH-12664","DOIUrl":"https://doi.org/10.5167/UZH-12664","url":null,"abstract":"The reaction of tert-butyl- or THP-protected mandelic thioacid (7a and 7b) with N,N,2,2-tetramethyl-2H-azirin-3-amine (2a) gave the dipeptide analogues tBu- and THP-Mns-Aibψ[CS]NMe 2 (8a and 8b, resp.) with a C-terminal thioamide group. Treatment of 8a with HCl gas in toluene led to 2-(1-rert-butoxybenzyl)-4,4-dimethyl-1,3-thiazole-5(4H)-one (9), which reacted with dimethylamine via ring opening to give tBu-Mnsψ[CSNH]Aib-NMe2 (lla), an isomer of8a with the thioamide group within the chain, i.e., the product of a sulfur migration. In the case of 8b, selective deprotection of the THP-hydroxy group was achieved by treatment with pyridinium p-toluenesulfonate (PPTS) in ethanol. Cyclization of the resulting Mns-Aibψ[CS]NMe 2 (13) yielded the 2-thioxomorpholin-5-one 10. In a similar manner, Boc-Val-SH (14) reacted with azirine 2b to give Boc-Val-Aibψ[CS]N(Me)Ph (15a), which was transformed to Fmoc-Val-Aibψ[CS]N(Me)Ph (15b) and further to Fmoc-Valψ[CSNH]Aib-N(Me)Ph (16) by treatment with ZnCl 2 in acetic acid. Coupling of two of these molecules via the 1,3-thiazol-5(4H)-one 17 yielded the endodithiopeptide Fmoc-Valψ[CSNH]Aib-Valψ[CSNH]Aib-N(Me)Ph (19).","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"83 1","pages":"195-206"},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70638389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The 1,4,5-trisubstitued 2,3-dihydro-1H-imidazole-2-thiones 1 react with electrophilic reagents via the S- or the N(3)-atom. The reaction with dimethyl acetylenedicarboxylate in methanol at room temperature occurs by the nucleophilic addition of the S-atom to give the corresponding 2-[(1H-imidazol-2-yl)sulfanyl]fumarates 4 in high yield. On the other hand, imidazole-2-thiones 1 react with phenylisocyanate in dichloromethane at room temperature to yield 2,3-dihydro-2-thioxo-1H-imidazole-1-carboxamides 5. The structures of both types of adducts were established by X-ray crystallography.
{"title":"Ambivalent Nucleophilicity of 1,4,5-Trisubstituted Imidazole-2-thiones in Reactions with Dimethyl Acetylenedicarboxylate and Phenylisocyanate","authors":"G. Mlostoń, T. Gendek, A. Linden, H. Heimgartner","doi":"10.5167/UZH-12637","DOIUrl":"https://doi.org/10.5167/UZH-12637","url":null,"abstract":"The 1,4,5-trisubstitued 2,3-dihydro-1H-imidazole-2-thiones 1 react with electrophilic reagents via the S- or the N(3)-atom. The reaction with dimethyl acetylenedicarboxylate in methanol at room temperature occurs by the nucleophilic addition of the S-atom to give the corresponding 2-[(1H-imidazol-2-yl)sulfanyl]fumarates 4 in high yield. On the other hand, imidazole-2-thiones 1 react with phenylisocyanate in dichloromethane at room temperature to yield 2,3-dihydro-2-thioxo-1H-imidazole-1-carboxamides 5. The structures of both types of adducts were established by X-ray crystallography.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"82 1","pages":"1561-1569"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70638058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reactions ofaryl isoselenocyanates 1 with 3-chloropropan- 1-ol (8) in the presence of sodium hydride in dichloromethane at room temperature gave 1,3-oxaselenan-2-imines 10 in fair yield. A reaction mechanism via nucleophilic attack of the alcoholate at the isoselenocyanate 1, followed by an 6-exo-teτ cyclization, is most likely.
{"title":"Synthesis of 1,3-Oxaselenan-2-imines from Isoselenocyanates","authors":"G. Sommen, H. Heimgartner","doi":"10.5167/UZH-50676","DOIUrl":"https://doi.org/10.5167/UZH-50676","url":null,"abstract":"The reactions ofaryl isoselenocyanates 1 with 3-chloropropan- 1-ol (8) in the presence of sodium hydride in dichloromethane at room temperature gave 1,3-oxaselenan-2-imines 10 in fair yield. A reaction mechanism via nucleophilic attack of the alcoholate at the isoselenocyanate 1, followed by an 6-exo-teτ cyclization, is most likely.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"81 1","pages":"1413-1418"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70654484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Stoeckli-Evans, I. Typilo, D. Semenyshyn, O. Sereda, R. Gladyshevskii
Thallium sulfide layers will be formed on the surface of low-density polyethylene (PE) if the PE layer is sulphured in a solution of higher polythionic acid H 2 S 33 O 6 , and then immersed in the alkaline solution of thallium(Ι) sulfate. Sulphur concentration increases on PE surface with the increase of the sulphurization time. The amount of thallium in the Tl x S y layers depends on a sulphur concentration sorbed-diffused into PE. Three phases TlS, Tl 2 S and Tl 2 S 2 were identified by X-ray diffraction analysis in thallium sulfide layers. Scanning Electron (SEM) and Atomic Force (AFM) microscopies were used to characterize surface morphology of thallium sulfide layers. The films deposited on the PE surface have a non-homogeneous structure and consist of separated islands. The process of their growth on PE surface starts from nucleation sites creating islands of TlS with diameter in tenths of microns which increase up to 9 μm during 1 h deposition.
将低密度聚乙烯(PE)表面的聚乙烯层在较高的聚硫酸h2s33o6溶液中硫化，再浸入硫酸铊(Ι)的碱性溶液中，会形成硫化铊层。PE表面的硫浓度随硫化时间的延长而增加。Tl x S y层中铊的含量取决于吸附扩散到PE中的硫浓度。通过x射线衍射分析，在硫化铊层中鉴定出Tl、tl2s和tl2s三个相。利用扫描电子显微镜(SEM)和原子力显微镜(AFM)对硫化铊层的表面形貌进行了表征。沉积在PE表面的薄膜具有非均匀结构，由分离的岛屿组成。它们在PE表面的生长过程从成核位点开始，形成直径为十分之一微米的tl岛，在沉积1 h后增加到9 μm。
{"title":"Crystal Structure of Terbium Potassium Octacyanotungstate(IV) Heptahydrate","authors":"H. Stoeckli-Evans, I. Typilo, D. Semenyshyn, O. Sereda, R. Gladyshevskii","doi":"10.1002/CHIN.200816005","DOIUrl":"https://doi.org/10.1002/CHIN.200816005","url":null,"abstract":"Thallium sulfide layers will be formed on the surface of low-density polyethylene (PE) if the PE layer is sulphured in a solution of higher polythionic acid H 2 S 33 O 6 , and then immersed in the alkaline solution of thallium(Ι) sulfate. Sulphur concentration increases on PE surface with the increase of the sulphurization time. The amount of thallium in the Tl x S y layers depends on a sulphur concentration sorbed-diffused into PE. Three phases TlS, Tl 2 S and Tl 2 S 2 were identified by X-ray diffraction analysis in thallium sulfide layers. Scanning Electron (SEM) and Atomic Force (AFM) microscopies were used to characterize surface morphology of thallium sulfide layers. The films deposited on the PE surface have a non-homogeneous structure and consist of separated islands. The process of their growth on PE surface starts from nucleation sites creating islands of TlS with diameter in tenths of microns which increase up to 9 μm during 1 h deposition.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"81 1","pages":"2031-2038"},"PeriodicalIF":0.0,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CHIN.200816005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51055023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Several dibenzoylbenzene dihydrazones were electrochemically oxidized into the corresponding bis-dimethyl acetals in a methanolic solution containing sodium methoxide and catalytic amount of KI. During electrolysis, the anolyte exhibited a characteristic deep purple, which strongly suggested that formation of a diazo compound as an intermediate. Interestingly, some of the diazo compounds could be isolated directly from the anolyte.
{"title":"Electrooxidative Conversion of Dibenzoylbenzene Dihydrazones into the Coreesponding Bis-Diazo Compounds and Bis-Dimethyl Acetals","authors":"M. Okimoto, K. Numata, Y. Takahashi","doi":"10.1071/CH05090","DOIUrl":"https://doi.org/10.1071/CH05090","url":null,"abstract":"Several dibenzoylbenzene dihydrazones were electrochemically oxidized into the corresponding bis-dimethyl acetals in a methanolic solution containing sodium methoxide and catalytic amount of KI. During electrolysis, the anolyte exhibited a characteristic deep purple, which strongly suggested that formation of a diazo compound as an intermediate. Interestingly, some of the diazo compounds could be isolated directly from the anolyte.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"79 1","pages":"1477-1482"},"PeriodicalIF":0.0,"publicationDate":"2005-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1071/CH05090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58662895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Urbaniak, G. Mlostoń, M. Gulea, S. Masson*, H. Heimgartner
The reaction of phosphonodithioformates 14 with diazomethane at –60°C yielded 2,5-dihydro-1,3,4-thiadiazoles 15 as unstable intermediates. Their structure was evidenced by the base-catalyzed elimination of methylsulfane leading to 1,3,4-thiadiazole-2-phosphonates. At ca. –35°C, thermal decomposition of 15 by N2-elimination led to reactive thiocarbonyl S-methylides 17. In the absence of trapping reagents, these 1,3-dipoles undergo a head-to-head dimerization leading to 1,4-dithianes 18. An intermediate zwitterionic dimer 19 was detected by 31P NMR spectroscopy. The initially formed thiocarbonyl S-methylide 17 as well as an open-chain zwitterionic dimer 20 was intercepted by methanol. Stable interception products were also obtained with S- and N-nucleophiles.
{"title":"Addition of Diazomethane to Phosphonodithioformates and Reactions of Phosphonylated Thiocarbonyl S-Methylides","authors":"K. Urbaniak, G. Mlostoń, M. Gulea, S. Masson*, H. Heimgartner","doi":"10.5167/UZH-67591","DOIUrl":"https://doi.org/10.5167/UZH-67591","url":null,"abstract":"The reaction of phosphonodithioformates 14 with diazomethane at –60°C yielded 2,5-dihydro-1,3,4-thiadiazoles 15 as unstable intermediates. Their structure was evidenced by the base-catalyzed elimination of methylsulfane leading to 1,3,4-thiadiazole-2-phosphonates. At ca. –35°C, thermal decomposition of 15 by N2-elimination led to reactive thiocarbonyl S-methylides 17. In the absence of trapping reagents, these 1,3-dipoles undergo a head-to-head dimerization leading to 1,4-dithianes 18. An intermediate zwitterionic dimer 19 was detected by 31P NMR spectroscopy. The initially formed thiocarbonyl S-methylide 17 as well as an open-chain zwitterionic dimer 20 was intercepted by methanol. Stable interception products were also obtained with S- and N-nucleophiles.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"79 1","pages":"1483-1494"},"PeriodicalIF":0.0,"publicationDate":"2005-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70659845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-01-01DOI: 10.1016/s0140-6701(02)80247-8
J. Słoczyński
{"title":"Methanol Synthesis from CO2 and H2 on Cu/ZnO/Al2O3-ZrO2 Catalysts. Catalytic Activity and Adsorption of Reactants","authors":"J. Słoczyński","doi":"10.1016/s0140-6701(02)80247-8","DOIUrl":"https://doi.org/10.1016/s0140-6701(02)80247-8","url":null,"abstract":"","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"75 1","pages":"733-742"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/s0140-6701(02)80247-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"55841683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-01-01DOI: 10.1016/S0074-6142(01)80095-4
S. Malinowski
{"title":"Physical and Chemical Properties RElated to Defect Structure of Oxides and Silicates Doped with Water and Carbon Dioxide","authors":"S. Malinowski","doi":"10.1016/S0074-6142(01)80095-4","DOIUrl":"https://doi.org/10.1016/S0074-6142(01)80095-4","url":null,"abstract":"","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"77 1","pages":"609-626"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0074-6142(01)80095-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"55809495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"THE REACTION OF SOME DITHIINODIQUINOLINES WITH POTASSIUM METHOXIDE AS A SOURCE OF 4-QUINOLINONES WITH 3-SULFIDE FUNCTION","authors":"A. Maślakiewicz, E. Bębenek","doi":"10.1002/CHIN.200008162","DOIUrl":"https://doi.org/10.1002/CHIN.200008162","url":null,"abstract":"","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"1 1","pages":"1783-1789"},"PeriodicalIF":0.0,"publicationDate":"2000-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CHIN.200008162","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50951051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-07-01DOI: 10.1080/00387019909350008
A. F. Shoair, A. El‐Bindary, A. El-Sonbati, R. Younes
Abstract A novel family of chelating bis-bidentate azodye compounds1 with Cu(II), Co(II), Ni(II), Fe(II), Hg(II), Pd(II), UO2(II), Fe(III), Cr(III), La(III), Ru(III) and Zr(IV) has been prepared and characterized on the basis of analytical, magnetic, 1H and 13C NMR, EPR and electronic spectral studies. Tentative structures for the polymeric complexes are proposed. The important IR bands and the main 1H and 13C signals are assigned and discussed relative to the molecular structure. Various EPR parameters for Cμ(II), have been calculated. The ligand acts as a dibasic bis-bidentate chelating agent coordinating through CO, N=N, COOH and OH groups by replacement of a proton from the two latter groups. Considerable interest has also been focused on the synthesis of the azo compound and its polymeric metal complex due to its wide potential applications. The thermal decomposition behavior of the complexes is also discussed.
{"title":"Stereochemistry of new nitrogen containg heterocyclicaldehydes. III. Novel bis-bidentate azodye compounds","authors":"A. F. Shoair, A. El‐Bindary, A. El-Sonbati, R. Younes","doi":"10.1080/00387019909350008","DOIUrl":"https://doi.org/10.1080/00387019909350008","url":null,"abstract":"Abstract A novel family of chelating bis-bidentate azodye compounds1 with Cu(II), Co(II), Ni(II), Fe(II), Hg(II), Pd(II), UO2(II), Fe(III), Cr(III), La(III), Ru(III) and Zr(IV) has been prepared and characterized on the basis of analytical, magnetic, 1H and 13C NMR, EPR and electronic spectral studies. Tentative structures for the polymeric complexes are proposed. The important IR bands and the main 1H and 13C signals are assigned and discussed relative to the molecular structure. Various EPR parameters for Cμ(II), have been calculated. The ligand acts as a dibasic bis-bidentate chelating agent coordinating through CO, N=N, COOH and OH groups by replacement of a proton from the two latter groups. Considerable interest has also been focused on the synthesis of the azo compound and its polymeric metal complex due to its wide potential applications. The thermal decomposition behavior of the complexes is also discussed.","PeriodicalId":20369,"journal":{"name":"Polish Journal of Chemistry","volume":"74 1","pages":"1047-1053"},"PeriodicalIF":0.0,"publicationDate":"1999-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00387019909350008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59182972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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