Benzocyclobutene in polymer synthesis. II. Solid state diels–alder polymerization utilizing an in situ generated diene and an alkyne

Abstract

SynopsisA novel class of aromatic h i d e AB-monomers with benzocyclobutene and an alkyne (primarily phenylethynyl group) as the reactive units have been prepared. The monomers have been utilized in thermally induced Diels-Alder polymerizations. The differential scanning calorimetric study of the AB-monomers provided two observations: (i) primary acetylene began its homopolymerization (202°C max.) before the electrocyclic ring opening of benzocyclobutene (270°C max.); (ii) the phenoxy group connecting between phenylacetylenyl group and the aromatic h i d e fragment suppressed polymerization in Diels-Alder fashion. Furthermore, thermoxidative stability evaluation on the cured samples (250°C for 8 h and then 350°C for another 8 h under N, atmosphere), carried out at 650°F (air) for 200 h, indicated the more rigid phenylethynyl phthalimide system was the most heat-resistant.

Sonogashira coupling with aqueous ammonia directed to the synthesis of azotolane derivatives

“…The following coupling products were obtained in a manner described above: 2-(phenylethynyl)aniline (3ab), 13 2-(phenylethynyl)phenol (3ac), 14 4-(phenylethynyl)phenol (3ad), 15 3-(phenylethynyl)aniline (3ae), 7b 3-(phenylethynyl)phenol (3af), 16 4-(trimethylsilylethynyl)aniline (3ba), 17 2-(trimethylsilylethynyl)aniline (3bb), 18 2-(trimethylsilylethynyl)phenol (3bc), 19 4-(trimethylsilylethynyl)phenol (3bd). 20 General procedure for Sonogashira-coupling reaction of 4-aminophenylethyne with aryl iodides.…”

Sonogashira Coupling with Aqueous Ammonia Directed to the Synthesis of Azotolane Derivatives.

“…The following coupling products were obtained in a manner described above: 2-(phenylethynyl)aniline (3ab), 13 2-(phenylethynyl)phenol (3ac), 14 4-(phenylethynyl)phenol (3ad), 15 3-(phenylethynyl)aniline (3ae), 7b 3-(phenylethynyl)phenol (3af), 16 4-(trimethylsilylethynyl)aniline (3ba), 17 2-(trimethylsilylethynyl)aniline (3bb), 18 2-(trimethylsilylethynyl)phenol (3bc), 19 4-(trimethylsilylethynyl)phenol (3bd). 20…”

Chemistry and properties of addition polyimides

“…It has been reported [88] that a certain bisbenzocyclobutene (BCB) and a commercially available low melting bismaleimide resin, COMPIMIDE 353, form compatible mixtures in a wide range of molar ratios, which after cure showed remarkable thermal oxidative stability and very high glass transition temperatures. Interestingly, it could be demonstrated that the thermal oxidative stability of nonstoichiometric COMPIMIDE 353/bisbenzocyclobutene copolymers is far superior to COMPIMIDE 353 homopolymer.…”