A vinyl-type polymer of norbornene containing a few pendant styrene groups obtained by copolymerization of norbornene and 1,4-divinylbenzene (1,4-DVB) was used as a macroinitiator in the reverse atom transfer radical polymerization (RATRP) of methyl methacrylate in conjunction with CuCl 2 /2,2 -bipyridine/2,2 -azobisisobutyronitrile (AIBN) as a catalyst. In the first step of the reaction, the structural characterization of the copolymers showed that norbornene and 1,4-divinylbenzene copolymerizations occur as a coordination mechanism and that true copolymers are formed by random copolymerization. With the initiation of copper dichloride and AIBN in the second step, the pendant styrene groups in the copolymers were quantitatively polymerized with methyl methacrylates, which allowed the successful synthesis of polynorbornene-based graft copolymers by RATRP mechanism. The analyses of the product by 1 H-and 13 C-NMR and GPC gel permeation chromatography (GPC) gave the verification of 'true' copolymer. Varying the monomer feed ratio controlled the thermal property of the graft copolymer.

Copolymerization of norbornene and 1,4-divinylbenzene was successfully performed using a β-ketoamine chelate nickel complex-methylaluminoxane, yielding random copolymer of norbornene and 1,4-divinylbenzene containing a few pendant styrene groups. With the initiation of copper dichloride and 2,2 -azobisisobutyronitrile, the pendant styrene groups were quantitatively polymerized with methyl acrylates, which allowed the successful synthesis of polynorbornene-based graft copolymers by reverse atom transfer radical polymerization mechanism. The analyses of the product by 1 H NMR and gel permeation chromatography gave the verification of 'true' copolymer. The thermal property of the graft copolymer was controlled by varying the monomer feed ratio.

Key indicators: single-crystal X-ray study; T = 293 K; mean (C-C) = 0.004 Å; R factor = 0.053; wR factor = 0.211; data-to-parameter ratio = 16.9.The structure of the title compound, C 25 H 23 N 3 O 2 , features a central pyrazole ring; an amine NH unit interacts with the ring CO unit through an intramolecular N-HÁ Á ÁO hydrogen bond [NÁ Á ÁO = 2.700 (2) Å ] CommentThis study is a continuation of our investigations of 4-(Z)-[(4-ethoxyphenylamino)(phenyl)methylene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-ones, which are readily synthesized by condensing 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone with a primary amine (A characteristic of such pyrazolones is the short intramolecular hydrogen bond between the amino NH unit and the carbonyl C=O unit.The title compound, (I), (Fig. 1), similarly exists as a monomeric molecule that features an intramolecular N-H···O hydrogen bond (Table 1) despite the presence of possible acceptor atoms in nearby molecules.Experimental 4-Benzoyl-3-methyl-1-phenyl-5-pyrazolone (1.20 g, 4.3 mmol) and 4-ethoxybenzenamine (0.62 g, 6.5 mmol) were dissolved in ethyl alcohol (20 ml). The solution was heated under reflux for 8 h. The solvent was removed and the pure product obtained upon recrystallization from ethyl alcohol (25 ml) in about 80% yield. Crystals of (I) were grown from ethanol at room temperature. Analysis calculated for C 25 H 23 N 3 O 2 : C 75.55, H 5.83, N 10.57%; found: C 75.52, H 5.85, N 10.58%. RefinementAll H atoms were geometrically placed (C-H = 0.93-0.97 Å, O-H = 0.82 Å, N-H = 0.85-0.86 Å) and refined as riding with U iso (H) = 1.2U eq (C) or 1.5U eq (O,N).

Key indicators: single-crystal X-ray study; T = 292 K; mean (C-C) = 0.005 Å; disorder in main residue; R factor = 0.063; wR factor = 0.183; data-to-parameter ratio = 14.4. organic compounds o3336 # 2007 International Union of Crystallography Experimental The compound was synthesized according to a reported procedure (Ding et al., 2001) and yellow blocks of (I) were grown from a dichloromethane/ diethyl ether solution (1:1 v/v) in about 75% yield. Analysis calculated for C 27 H 35 N 3 O 2 : C 74.79, H 8.14, N 9.69%; found: C 74.85, H 8.36, N 9.79%. RefinementIt is analogous to the examples (Sun et al., 2006), the pentyl chain (C18 to C12) is disordered over two positions; the occupancy factors refined to 0.52 (1):0.48 (1). The pairs of 1,2-related and 1,3-related distances were restrained to be equal within 0.01 Å. The H atoms were positioned geometrically (C-H = 0.93-0.97 Å) and refined as riding with U iso (H) = 1.2U eq (C) or 1.5U eq (methyl C).