0000000000266293

AUTHOR

Franc Požgan

showing 5 related works from this author

Chemical recycling of polyenaminones by transamination reaction via amino–enaminone polymerisation/depolymerisation

2019

Abstract Novel oligo- and polyenaminones with Mw ∼ 3000 Da were prepared in excellent yields by amino–enaminone ‘click’ polymerisation of 1,3- and 1,4-bis[3-(dimethylamino)acryloyl]arenes with 1,3- and 1,4-phenylenediamine. The obtained oligomers and polymers were depolymerised quantitatively to the starting bis-enaminones and diamines by treatment with excess dimethylamine in ethanol at 50 °C. This simple polymerisation/depolymerisation method allows for a closed-loop recycling of polyenaminone-based materials. UV light absorbance at wavelengths below 470 nm indicates promising optical properties of these polymers.

chemistry.chemical_classificationLight absorbanceEthanolPolymers and PlasticsTransaminationOrganic ChemistryGeneral Physics and Astronomy02 engineering and technologyPolymer010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciences0104 chemical scienceschemistry.chemical_compoundchemistryPolymerizationMaterials Chemistry0210 nano-technologyDimethylamineEuropean Polymer Journal
researchProduct

Absolute Configuration Determination of 2,3-Dihydro-1H,5H-pyrazolo[1,2-a]pyrazoles Using Chiroptical Methods at Different Wavelengths

2016

A correlation between the absolute configuration and chiroptical properties of nonracemic 1,6,7-trisubstituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazoles was studied. A series of 16 novel representatives were prepared by Cu-catalyzed [3 + 2] cycloadditions of racemic (Z)-2-benzylidene-5-oxopyrazolidin-2-ium-1-ides to tert-butyl (S)-(3-oxopent-4-yn-2-yl)carbamate, and their structures were determined by NMR, VCD, ECD, and X-ray diffraction. A clear correlation between the sign of specific rotation and configuration at position C(1) allows for easy determination of the absolute configuration of 1,6,7-trisubstituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazoles by ECD and NMR. While VCD, requirin…

chemistry.chemical_compoundWavelength010405 organic chemistryChemistryStereochemistryOrganic ChemistryAbsolute configurationPhysical chemistrySpecific rotation010402 general chemistry01 natural sciences0104 chemical sciencesSign (mathematics)The Journal of Organic Chemistry
researchProduct

CCDC 1497003: Experimental Crystal Structure Determination

2016

Related Article: Eva Pušavec Kirar, Uroš Grošelj, Amalija Golobič, Franc Požgan, Stefan Pusch, Carina Weber, Lars Andernach, Bogdan Štefane, Till Opatz, Jurij Svete|2016|J.Org.Chem.|81|11802|doi:10.1021/acs.joc.6b02270

Space GroupCrystallographybenzyl (6-(2-((t-butoxycarbonyl)amino)propanoyl)-3-isopropyl-5-(4-nitrophenyl)-1-oxo-23-dihydro-1H5H-pyrazolo[12-a]pyrazol-2-yl)carbamateCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
researchProduct

CCDC 1497004: Experimental Crystal Structure Determination

2016

Related Article: Eva Pušavec Kirar, Uroš Grošelj, Amalija Golobič, Franc Požgan, Stefan Pusch, Carina Weber, Lars Andernach, Bogdan Štefane, Till Opatz, Jurij Svete|2016|J.Org.Chem.|81|11802|doi:10.1021/acs.joc.6b02270

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters(+)-t-butyl (1-(1-(4-nitrophenyl)-5-oxo-7-phenyl-67-dihydro-1H5H-pyrazolo[12-a]pyrazol-2-yl)-1-oxopropan-2-yl)carbamateExperimental 3D Coordinates
researchProduct

CCDC 1497005: Experimental Crystal Structure Determination

2016

Related Article: Eva Pušavec Kirar, Uroš Grošelj, Amalija Golobič, Franc Požgan, Stefan Pusch, Carina Weber, Lars Andernach, Bogdan Štefane, Till Opatz, Jurij Svete|2016|J.Org.Chem.|81|11802|doi:10.1021/acs.joc.6b02270

Space GroupCrystallographyCrystal SystemCrystal Structure(-)-t-butyl (1-(1-(4-nitrophenyl)-5-oxo-7-phenyl-67-dihydro-1H5H-pyrazolo[12-a]pyrazol-2-yl)-1-oxopropan-2-yl)carbamateCell ParametersExperimental 3D Coordinates
researchProduct