Oxazoline function

A novefroute to l//-l-benzazepin-9-carboxylic acid, which capitalizes on the reactivity towards metal exchange of a methoxy group ortho to an oxazoline function, is outlined in Scheme 15 (81JOC783). 

In this example oxazoline functions as nucleophile and /3-propiolactone as electrophile. 

Another rhodium based system has been reported by Murai and coworkers [62] to be effective for catalyzing Si-F exchange between aromatic C-F bonds adjacent to acyl or oxazoline functionality. 

As shown in Table 5.21, blends of PA and PS have been compatibilized through graft copolymer formation between PA amine or acid end-groups and oxazoline-functionalized styrene copolymer. 

Vainio et al. [1997, 1996a] have compatibilized PEST/PP blends by graft copolymer formation between acid-terminated polyester and oxazo-line-grafted PP. Specifically, 30 parts PBT was mixed with 0-70 parts PP and 0-70 parts PP-g-oxazoline in an internal mixer at 250°C or TSE at 240°C. Blends were characterized by SEM, torque rheometry, DMA, and DSC. Oxazoline-functionalized PP was prepared by grafting PP... 

Oxazoline functionalization of a singly bonded C o dimer was achieved via a one-pot reaction of CgoECBn with OH and aromatic nitriles (14JOC197). A simple metal-free heterocyclization of uracil amides 158 was efficiendy carried out with hypervalent iodine Phl(OAc)2 in the presence of BF3 OEt2 affording pyrimidine-annulated oxazolines 159 in high yields (14TL5625). 

PEST/PO blends have been compatibilized through graft copolymer formation by reaction of polyester carboxylic acid end-groups with pendent oxazoline groups on an appropriate PO. The copolymer contains a new esteramide linkage. Womer et al. (1997) have blended 0-20 parts oxazoline-functionalized rubbers containing more than one oxazoline group per chain with 100-80 parts acid-terminated PBT in... 

Lee and Park (2001) prepared compatibilized PC-PBT-PS blends through reacting PBT with oxazoline-functionalized PS. See Becker and Schmidt-Naake (2003) for compatibilized blends of PC with oxazoline-functionalized SAN and... 

Lee and Park (2000) found evidence for copolymer formation in blends of anhydride-terminated PC and oxazoline-functionalized PS prepared in a Haake mixer. Blends were characterized by torque rheometry, SEM, FTIR, NMR, and mechanical properties. Anhydride-terminated PC was prepared by reaction of PC phenolic end-groups with trimellitic anhydride acid chloride (cf. Hathaway and Pyles 1988, 1989). 

Soares et al. (2004) prepared blends of partially hydrolyzed EVAc and NBR using oxazoline-functionalized NBR. Blends were characterized by techniques including mechanical properties, morphology, selective solvent extraction, and FTIR. 

PO/styrene copolymer blends have been compatibilized through cross-linked copolymer formation between acid-functionalized PO and oxazoline-functionalized PS (Table 5.59). Anhydride-functionalized PO is also effective in these blends since some acid groups may be present from ring-opened anhydride. Oxazoline groups are most frequently introduced into PS by copolymerization of styrene with isopropenyl oxazoline (IPO). 

Sundararaj et al. (1995) have prepared blends containing PP-MA and oxazoline-functionalized PS. A graft copolymer may form through reaction between pendent oxazoUne groups on PS and terminal acid groups (from some hydrolysis of anhydride groups) on PP. Specifically, 80 parts S-lPO (1 % IPO) was blended with 20 parts PP-MA (0.1 % MA) in either an internal mixer at 200 °C or in a TSE. The blends were characterized by selective solvent extraction and SEM. Morphology... 

Anionic and Cationic Polymerizations o Radical Polymerization Advances o Coordination Polymerizations 0 Step-Growth Polymerization Advances 0 Synthesis of Tactic Polymers o Stereoblock Copolymers o Dispersion Polymerizations o Cellulosic Graft Copolymers o Diels-Alder Polymer Forming Reactions o A New Path To Phenolic Resins o Nitrogen Heterocycle Polymerizations o Optically Active Polymers o Poly (Phenylene Sulfide) o Poly (Aryl Ethers) o (Poly (Aryl Ether Sulfones) o Epoxy and Isocyanate Resin Replacement o Azlactone Functionalized Oligomers o Epoxy Resin-Isocyanate Reactions o Chelating Polymers o Oxazoline Functionalized Polymers o Poly (Alkyl Methacrylates) o Macromers... 

SCHEME11.2 Copolymerization of propylene with oxazoline-functionalized monomers. 

Figure 1. Reaction scheme of oxazoline-functionalized polystyrene with PBT.

Oxazoline-functionalized polystyrene (RPS and RAS series, Nippon Shokubai Co., Ltd.) had been used in PC/ABS blends as the reactive compatibihzer. The third pol3rmer component (for example, polycaprolactone ), that has the median properties between two polymer components, can also be added as a compatibihzer. In miscible blends most properties fall below the arithmetic average of properties of the two components. Good, commercially successful blends have the averaged properties of two pol3rmer components. 

Scheme 10.62 Oxazoline-functionalized NPN-tridentate ligands-supported dipalladium(l) compounds 125 and 126.

Alkylation of the lithioarene 19 by halogenoalkane affords 20, which on hydrolysis in aqueous acid leads to the 2-substituted benzoic acid 21. Overall, the oxazoline function serves as a vehicle for the ortho-alkylation of a benzoic acid, which is not possible in the presence of a free COOH group [298]. 

Schafer et al. [15] have also investigated the reaction kinetics of an oxazoline functionalized butadiene-co-acrylonitrile copolymer with a poly(ethylene-co-methacrylic acid). A two-layer specimen was used for the kinetics study. FTIR spectroscopy was carried out on the two-layer specimen annealed at different temperatures from 170 to... 

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