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Bezpośrednia synteza azydków i tioli organicznych pochodnych glikolu etylenowego w zmodyfikowanej reakcji Appela

Stefaniak M., Jasiński M., Urbaniak K., Romański J., Seliger P., Gutowska N

Chemik

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2014

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Vol. 68, nr 7

592--599

PL

Klasyczną metodę konwersji alkoholi pierwszorzędowych w odpowiednie halogenki alkilowe z użyciem trifenylofosfiny oraz tetrahalogenometanu, tzw. reakcję Appela, zaadoptowano do bezpośredniej syntezy terminalnych tioli i azydków organicznych pochodnych glikolu etylenowego oraz jego siarkowego analogu. W kluczowym etapie opisanej procedury one-pot, otrzymane in situ, w reakcji z N-bromosukcynimidem (NBS), odpowiednie dibromopochodne zostały przekształcone w związki docelowe w reakcji z nukleofilem siarkowym lub azotowym. Wybrane diazydki wykorzystano w syntezie nowych układów makrocyklicznych, które przetestowano pod kątem ich właściwości kompleksotwórczych.

EN

Classical method of conversion of primary alcohols into corresponding alkyl halides by usage of triphenylphosphine and tetrahalogenated methane, so-called Appel reaction, was adopted for the direct synthesis of terminal organic thiols and azides derived from ethylene glycol and its sulfurated analogue. In key step of the presented ‘one-pot’ protocol, corresponding dibromides, generated in situ via reaction with N-bromosuccinimide (NBS), were converted into desired products by treatment with appropriate sulfur or nitrogen nucleophile. A series of diazides and dithiols derived from (poly)ethylene glycols and their sulfur analogues were obtained. Selected diazides were utilized for the construction of novel macrocyclic systems, that were tested incontext of their complexing properties.

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Reaction of 1,2-Di(1-adamantyl)-2-thioxoethanone with Diazomethanes; 1,3- versus 1,5-Dipolar Electrocyclization of a Sterically Crowded Thiocarbonyl S-Methylide

Mlostoń G., Urbaniak K., Nomura T., Nakayama J., Heimgartner H.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 11

1945-1951

EN

The reaction of 1,2-di(1-adamantyl)-2-thioxoethanone (4c) with diazomethane and 2-diazopropane yielded 2-acylthiiranes 6a and 6b, respectively, and no 1,3-oxathioles of type 7 were formed. The reaction course is explained via [2+3]-cycloaddition, elimination of N2, and 1,3-dipolar electrocyclization of the in ter me di ate acyl-substituted thiocarbonyl ylides of type 1. The fail ure of the competitive 1,5-dipolar electrocyclization is a result of the sterically unfavor able conformation 1a.

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Preparation and Structure of Optically Active Imidazolium Tetrafluoroborates; in Search of New Chiral Ionic Liquids

Mlostoń G., Mucha P., Tarka R., Urbaniak K., Linden A., Heimgartner H.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 6

1105-1114

EN

Enantiomerically pure (R)-1-(1-phenylethyl)imidazoles 4a,b can be prepared conveniently from alfa-(hydroxyimino)ketones 1, (R)-1-phenylethylamine and form aldehyde, fol lowed by deoxygenation with Raney-Ni. Similarly, the reaction with (R,R)-trans-cyclohexane-1,2-diamine yields enantiomerically pure (R,R)-trans-1,1'-cyclohexane-1,2-diyl)imidazoles 4c,d. Alkylation of these imidazole derivatives with alkylbromides leads to the corresponding 3-alkylimidazolium bromides 6 and 8, respectively, which on treatment with sodium tetrafluoroborate are transformed into the correspond ing tetrafluoroborates 7 and 9. Whereas some of the imidazolium salts 7 show properties of chiral ionic liquids, the bis-imidazolium tetrafluoroborates 9 are high-melting crystalline materials.

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Reactions of 9H-Fluorene-9-thione with (Trimethylsilyl)diazomethane

Mlostoń G., Urbaniak K., Linden A., Heimgartner H.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 11

1849-1860

EN

he [3+2]-cycloaddition of (trimethylsilyl)diazomethane (7) with 9H-fluorene-9-thione (1) at –60°C yields the spirocyclic 2,5-dihydro-5-trimethylsilyl-1,3,4-thiadiazole 10, which eliminates nitrogen at room temperature to give the 1,4-dithiane derivative 13 by dimerization of the intermediate fluorenethione (trimethylsilyl)methanide (11). This thiocarbonyl ylide can be trapped by 1 to give the 2-trimethylsilyl-1,3-dithiolane 14 via [3+2]-cycloaddition. Further more, the 1,3-di pole 11 under goes successfully [3+2]- cycloadditions with the C=S group of the phosphonyldithioformate 15 as well as with the C=C dipolarophiles maleic an hydride (18a) and N-(cyclohexyl)maleimide (18b). The structures of 13 and 14 have been established by X-ray crystallography.

5

Addition of Diazomethane to Phosphonodithioformates and Reactions of Phosphonylated Thiocarbonyl S-Methylides

Urbaniak K., Mlostoń G., Gulea M., Masson S., Heimgartner H.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 9

1483-1494

EN

The reaction of phosphonodithioformates 14 with diazomethane at -60 graduate 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 graduate 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.