N-ヘテロサイクリックカルベンのプロトン転送ポリメリゼーション:モノマーと触媒の範囲とジメタクリレットを不飽和ポリエステルに変換するメカニズム
Miao Hong1, Xiaoyan Tang1, Laura Falivene2,3
1Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523-1872, United States.
Journal of the American Chemical Society
|January 19, 2016
まとめ
N-ヘテロサイクリックカルベン (NHC) 誘導型陽子転送ポリメリゼーション (HTP) は,ジメタクリラートから不飽和ポリエステルを生成する. この研究では,HTPのメカニズム,触媒の活性,および自己固化特性を持つバイオマス由来ポリエステルの詳細が示されています.
科学分野:
- ポリマー化学
- 有機合成
- カタリシス
背景:
- N-ヘテロサイクリックカルベン (NHCs) は有機合成における汎用的な触媒である.
- プロトン転送ポリメリゼーション (PTP) は,プロティックモノマーを必要とするポリメリゼーション方法である.
- ダイメタクリレート (DMA) は,プロティック群を欠く一般的なモノマーであり,従来のPTPでの使用を制限しています.
研究 の 目的:
- デメタクリラート (DMA) を不飽和ポリエステルに変換するためのN-ヘテロサイクリックカルベン (NHC) 誘導型陽子転送ポリメリゼーション (HTP) を調査する.
- この新しいHTPのメカニズム,モノメアの範囲,および触媒構造-活性関係を調査する.
- 新しいNHC触媒とその誘導体を合成し,特徴づけること.
主な方法:
- NHC触媒を用いた様々なDMAの実験的ポリメリゼーション
- NHC触媒とその誘導体の合成と構造的特徴付け
- HTPのメカニズムと触媒の振る舞いを明らかにするための理論的/計算的調査.
主要な成果:
- 6つの異なるDMAをNHCで触媒化されたHTPで不飽和ポリエステルに成功させた.
- バイオマス製のフルフリルジメタクリレート基ポリエステルの自己固化能力の特定
- 最も活性な触媒として特定のNHC誘導体 ((OMe2) TPT) を示し,最も高い分子量を持つポリマーを生成する構造-活性関係研究.
結論:
- NHCで触媒化されたHTPは,DMAから不飽和ポリエステルを合成する有効な方法である.
- HTPのメカニズムは,エナミンの中間体,結合添加,陽子の移転,およびNHCの放出による段階的な増殖を伴う.
- 計算による研究は,提案されたメカニズムを支持し,中間物の熱力学的安定性に基づいて観察された触媒の性能を説明する.
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