RESUMO
A facile complexation of formaldehyde with the water-tolerant frustrated Lewis pair (FLP) B(C6F5)3/PtBu3 and its Al-analog under ambient conditions is reported. Unprecedented formaldehyde adducts 1, 2 and 4 have been identified and crystallographically characterized.
RESUMO
Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained by the multicomponent polymerization of CO2 , propylene oxide, maleic anhydride, and allyl glycidyl ether. Poly(ether carbonate)s with ABXBA multiblock structures were obtained by sequential addition of mixtures of propylene oxide/maleic anhydride and propylene oxide/allyl glycidyl ether during the polymerization. The simultaneous addition of both monomer mixtures provided poly(ether carbonate)s with AXA triblock structures. Both types of polyunsaturated poly(ether carbonate)s are characterized by diverse functional groups, that is, terminal hydroxy groups, maleate moieties along the polymer backbone, and pendant allyl groups that allow for versatile polymer chemistry. The combination of double bonds substituted with electron-acceptor and electron-donor groups enables particularly facile UV- or redox-initiated free-radical curing. The resulting materials are transparent and highly interesting for coating applications.
RESUMO
The choice of the anion has a surprisingly strong effect on the incorporation of CO2 into the polymer obtained during the zinc-catalysed copolymerisation of CO2 and cyclohexene oxide. The product span ranges from polyethercarbonates, where short polyether sequences alternate with carbonate linkages, to polycarbonates with a strictly alternating sequence of the repeating units. Herein, we report on the influence of the coordination ability of the anion on the selectivity and kinetics of the copolymerisation reaction.
RESUMO
A versatile and high yielding one-pot hydroformylation/Strecker synthesis is reported for the synthesis of various alpha-aminonitriles. This methodology allows functionalization of dendrimers (e.g. polyamines 4-7) and hyper branched polymers (e.g. polyallyl glycerol 12) to give corresponding dendritic structures with alpha-aminonitriles and/or amino acids in the outer shell in good to excellent yields.