Seminar

Seminar

Investigating Enantioselective Catalysis Controlled by Phosphorus Ligands and N-Heterocyclic Carbenes

  • POSTED DATE : 2021-03-05
  • WRITER : 화학과
  • HIT : 393
  • DATE : 2021년 3월 11일(목) 오후 4시 30분
  • PLACE : Webex

세미나가 다음주 목요일(3월 11일)에 개최됩니다.

많은 참여 부탁드립니다.


감사합니다.

 

===============================================================================

제  목 : Investigating Enantioselective Catalysis Controlled by Phosphorus Ligands and N-Heterocyclic Carbenes


연  사 : 이안수 박사(한국과학기술연구원(KIST))


일  시 : 2021년 3월 11일(목) 오후 4시 30분


<Webex참여>

방번호: 170 974 2739

링크: https://skku-ict.webex.com/meet/chem

 

================================================================================

Investigating Enantioselective Catalysis Controlled by
Phosphorus Ligands and N-Heterocyclic Carbenes


Ansoo Lee


Brain Science Institute, KIST, Seoul 02792, Korea
E-mail: alee@kist.re.kr


Chemical reaction is a crucial component of our everyday lives. The most powerful and
efficient chemical reactions commonly use catalysis to control reactivity and selectivity. Thus,
the discovery of new catalyst and catalysis concepts with broad utility beyond established
reactivity will give a great impact on academic and industrial organic synthesis.
In the first part, I will discuss our discovery on new phosphorus ligand design for transition
metals. We have developed a new class of bicyclic bridgehead phosphoramidite (briphos)
ligands.1 The geometrical constraints in briphos with respect to its monocyclic analogs enhance
π-acceptor ability. The enhanced π-acceptor ability gives dramatic ligand acceleration effect in
low-valent transition metal-catalyzed reactions. Furthermore, development of chiral briphos
leads to asymmetric induction in Rh(I)-catalyzed conjugate additions.2,3
In the second part, I will discuss our recent finding on a new N-heterocyclic carbene (NHC)
organocatalysis. We have developed a direct decarboxylative strategy for the generation of azao-
quinone methides (aza-o-QMs) by NHC catalysis.4 Aza-o-QMs react with trifluoromethyl
ketones through a formal [4+2] manifold to access highly enantioenriched dihydrobenzoxazin-
4-one products, which can be converted to dihydroquinolones through an interesting
stereoretentive aza-Petasis–Ferrier rearrangement sequence.


References
1. Lee, A.; Ahn, S.; Kang, K.; Seo, M.-S.; Kim, Y.; Kim, W. Y.; Kim, H. Org. Lett. 2014, 16,
5490-5493.
2. Lee, A.; Kim, H. J. Am. Chem. Soc. 2015, 137, 11250-11253.
3. Lee, A.; Kim, H. J. Org. Chem. 2016, 81, 3520-3527.
4. Lee, A.; Zhu, J. L.; Feoktistova, T.; Brueckner, A. C.; Cheong, P. H.-Y.; Scheidt, K. A.
Angew. Chem. Int. Ed. 2019, 58, 5941-5945.