The catalytic performance of Ru–NHC alkylidene complexes: PCy₃ versus pyridine as the dissociating ligand

• Stefan Krehl,
• Diana Geißler,
• Sylvia Hauke,
• Oliver Kunz,
• Lucia Staude and
• Bernd Schmidt

Beilstein J. Org. Chem. 2010, 6, 1188–1198, doi:10.3762/bjoc.6.136

• loading of 2 mol % was sufficient to achieve a 92% conversion within one hour (Figure 4). Ring closing metathesis of acrylates Having established the beneficial effect of acetic acid for the ring closing metathesis reaction of allyl ether 1 catalyzed by H, we were interested to see if a similar effect

• ). Toluene was preferred over dichloromethane, because reactions are more conveniently conducted at elevated temperatures in this solvent. The acrylates 3 investigated in ring closing metathesis reactions with catalysts D, E and H are listed in Figure 5, together with the resulting unsaturated lactones 4

• . Results for the ring closing metathesis of acrylates 3a–g are summarized in Table 2. Lactones 4b–f [50] are accessible in preparatively useful yields with catalyst loadings of 2.5 mol % to 5.0 mol % if catalysts D and E are used. Conversions observed with catalyst H under otherwise identical conditions

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• [32]. For a batch process with an initiator in the aqueous phase, it was found that the copolymerization followed the Mayo–Lewis equation despite the huge difference of solubility of the monomers in the aqueous continuous phase. Fluorinated monomers (fluoroalkyl acrylates) could be easily polymerized

Novel 2-(ω-phosphonooxy-2-oxaalkyl)acrylate monomers for self-etching self-priming one part adhesive

• Joachim E. Klee and
• Uwe Lehmann

Beilstein J. Org. Chem. 2010, 6, 766–772, doi:10.3762/bjoc.6.95

• 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. Keywords: adhesion to enamel and dentin; hydrolysis stable 2-(ω-phosphonooxy-2-oxaalkyl)acrylates; phosphorylation using POCl3; polymerization enthalpy; shear bond strength; Introduction Dental

• moieties takes place in a similar manner to carboxylic acid esters, and to establish whether acidic molecules with 2-(ω-phosphonooxy-2-oxaalkyl)acrylate moieties exhibit the same adhesive performance as their ester analogues. Results and Discussion A series of novel 2-(ω-phosphonooxy-2-oxaalkyl)acrylates 3

Synthesis, characterization and photoinduced curing of polysulfones with (meth)acrylate functionalities

• Cemil Dizman,
• Sahin Ates,
• Lokman Torun and
• Yusuf Yagci

Beilstein J. Org. Chem. 2010, 6, No. 56, doi:10.3762/bjoc.6.56

• polymerization and conversion were evaluated. Thermal properties of the photochemically cured films were studied by differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA). Keywords: acrylates; photoinitiated polymerization; polysulfone; UV-curable oligomers; Introduction Polysulfones

• range capable of inducing rapid polymerization to form insoluble networks [16]. Because of their high reactivity leading to fast polymerization [17], multifunctional (meth)acrylates are the most commonly used monomers for many applications [18][19][20][21][22]. The activity of the (meth)acrylates