Hyeung‐geun Park
서울대학교 약학대학 · 화학
Hyeung-geun Park 교수의 연구실은 주로 비대칭 촉매 반응, 특히 키토산 유도체를 기반으로 한 단백질-소재 상호작용을 연구합니다. 특히 페어트랜스퍼 촉매를 활용한 고대칭적 알킬화 및 알릴레이션 반응을 통해 자연산 및 비자연산 키랄 α-아미노산의 효율적이고 고선택적 합성을 개발하고 있습니다. 이는 스피로옥시인도론 유도체를 포함한 생활물질의 대량 합성 및 생물학적 활성 연구에 응용 가능합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Phase-transfer catalysis is one of the most useful methodologies for practical syntheses given its operational simplicity and mild reaction conditions that enable its application in industrial processes. Cinchona alkaloids have been a popular, natural source of practical organocatalysts due largely to their excellent commercial availability and low cost. Since the first Cinchona alkaloid-derived phase-transfer catalysts was disclosed in 1981, diverse generations of Cinchona-derived phase-transfe
A dimeric Cinchona alkaloid ammonium salt, α,α′-bis[O(9)-allylcinchonidinium]-m-x ylene dibromide 4, has been developed as a new efficient phase-transfer catalyst; the catalytic enantioselective alkylation of N-(diphenylmethylene)glycine tert-butyl ester using 4 provided 7 in a high enantiomeric excess (90–99% ee).
Potenzielle Katalysatoren für industrielle Syntheseprozesse zur Herstellung natürlicher und nichtnatürlicher chiraler α-Aminosäuren sind die dimeren, auf Naphthalin basierenden Cinchona-Alkaloide 1 aufgrund der milden Reaktionsbedingungen und hohen katalytischen Effizienz (hohe Ausbeuten und ee-Werte). Sie fungieren als Phasentransferkatalysatoren bei der Alkylierung eines Glycin-Derivats. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2
A new efficient and concise enantioselective synthetic method for (-)-horsfiline is reported. (-)-Horsfiline could be obtained from diphenylmethyl tert-butyl malonate in 9 steps (32%,>99% ee) by using the enantioselective phase-transfer catalytic allylation (91% ee) as the key step. This approach can be applied as a practical route for the large-scale synthesis of spirooxindole natural products, which enables a systematic investigation of their biological activity to be performed.
The phase-transfer catalytic alkylation of N,N-dialkylmalonamic tert-butyl esters in the presence of 1 mol% of (S,S)-3,4,5-trifluorophenyl-NAS bromide afforded highly enantioselective (S)-mono-alpha-alkylated products (up to 96% ee), which could be readily converted into versatile chiral building blocks without loss of chirality.
