0000000001305727
AUTHOR
Jurij Svete
Chemical recycling of polyenaminones by transamination reaction via amino–enaminone polymerisation/depolymerisation
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.
Absolute Configuration Determination of 2,3-Dihydro-1H,5H-pyrazolo[1,2-a]pyrazoles Using Chiroptical Methods at Different Wavelengths
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…
CCDC 1497003: Experimental Crystal Structure Determination
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
CCDC 1497004: Experimental Crystal Structure Determination
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
CCDC 1497005: Experimental Crystal Structure Determination
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