안녕하세요.

다음주 목요일(11월 19일) 세미나가 진행됩니다.

많은 참석 부탁드립니다.

감사합니다.

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제 목 : Making Small Molecules/Large Molecules, It’s all Syntheses

연 사 : 김정곤 교수 (전북대학교)

일 시 : 2015년 11월 19일 (목) 오후 4시 30분

장 소 : 화학관 세미나실 (330226호실)

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Making Small Molecules/Large Molecules, It’s all Syntheses

1. Mechanism Guided Development of Robust C-H Amination.

                          2. Metal-free Hydrosilylation Polymerization

In this seminar, two examples of organic and polymer syntheses based on catalysis are presented.

In the first half, a mechanistic study driven development of highly active Rh(III) catalyzed C-H amination will be presented. The clear identification of a rate control factor on Cp*Rh(III) catalyzed amidation allowed us to develop a new type of amidating reagents. The new amidating reagent, 1,4,2-dioxazol-5-one is not only reactive but also has many favorable features of broad synthetic scope, safe operations, and scalability. The whole development process of the mechanistic investigation, finding new amino source, and scale-up study will be discussed.

In the second half, the new route to polycarbosilanes using a non-metal catalyst is presented. Unique catalytic behaviors of boranes, especially B(C6F5)3, are of special interest. Its high and versatile reactivity has widely applied to areas ranging from hydrosilylation and reduction of simple substrates to biomass conversion into valuable hydrocarbons. Along with many interesting reactions and applications, making or manipulation of macromolecules by boranes is highly anticipated to bring new structures and properties. We recently showcased it by the first example of metal-free hydrosilylation polymerization between dienes and disilanes by B(C6F5)3, which successfully replaced precious transition-metal-based systems. Under the easy-to-handle and mild conditions, various combinations of dienes and disilanes produced polycarbosilanes with a broad range of structures and properties. Their distinctive reactivity and selectivity are discussed herein.

[1] Park, Y.; Park, K. T.; Kim, J. G.*; Chang, S.* J. Am. Chem. Soc. 2015, 137, 4534.

[2] Kim, D. W.; Joung, S.; Kim, J. G.*; Chang, S.* Angew. Chem. Int. Ed. 2015, Early View.