The 0.3 ± 5 g scale syntheses of the 2,2':6',2''-terpyridines 3, 6, 9, and 10 are described. The pyridine units are connected to one another by Pd-catalyzed crosscoupling reactions. This method allows the easy introduction of halogen, stannyl, and boronic ester functionalities at positions C-5 and C-5''; this results in a novel functionality pattern for terpyridines that considerably widens the applicability of this class of tridentate ligands for supra-and macromolecular applications. The feasibility of growth reactions with these novel terpyridines was demonstrated by the synthesis of compounds 12 a ± c.
A 0.5-11 g scale synthesis of the 5,5'-disubstituted 2,2'bipyridines is described. The pyridine units are connected to one another by Pd-catalyzed cross-coupling reactions. This method allows one to introduce bromo functions and flexible chains at the terminal phenyls which optimizes this class of bidentate ligands for supra-and macromolecular applications.
SummaryNovel N-alkyl-N-(phosphonoethyl) substituted mono-, bis- and tris(meth)acrylamides 3 were synthesized by two different three-step reactions and characterized by IR, 1H NMR and 13C NMR spectroscopy as well as refractive index and viscosity. The phosphonoethyl substituted (meth)acrylamide monomers show improved hydrolytic stability compared to carboxylic esters. The highest stability was found for the phosphonoethyl substituted acrylamide monomers. Acrylamides have a larger polymerization enthalpy ranging from −50 to −70 kJ·mol−1 per double bond compared to methacrylamides which show −8.57 to −25.1 kJ·mol−1 per double bond. Depending on their structure (meth)acrylamides 3 exhibit an adhesion to enamel and dentin up to 19.5 MPa. The monomer 3c shows the highest adhesion values to both substrates, namely 15.3 ± 3.4 MPa to enamel and 18.5 ± 2.3 MPa to dentin.
SummaryNovel hydrolysis stable 2-(ω-phosphonooxy-2-oxaalkyl)acrylate monomers 3 with phosphoric acid moieties were synthesized by a three step synthesis via Baylis–Hillman reaction of ethyl acrylate and formaldehyde, and subsequent etherification of the obtained product with diols and phosphorylation using POCl3. The polymerization enthalpy of 2-(ω-phosphonooxy-2-oxaalkyl)acrylates 3 as measured by DSC ranges from −29 to −53 kJ·mol−1. The shear bond strength of adhesive compositions 4, comprising of polymerizable acids 3, ranges from 5.8 to 19.3 MPa on enamel and from 8.7 to 16.9 MPa on dentin.
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