Stereocontrolled Dihydroxylation Reactions of Acyclic Allylic Amines

Abstract

초 록 비고리 알릴아민 화합물의 이중알코올화 반응은 아미노 다이올 구조를 도입할 수 있는 효율적인 합성법으로 아미노 다이올 구조를 포함하는 다양한 생리활성 천연물의 효율적인 합성에 적용될 수 있다. 본 리뷰에서는 기질 그 자체, 혹은 카이랄 리간드를 이용한 다양한 입체선택적 이중알코올화 반응들을 소개하고 이를 실제 천연물의 합성에 적용 한 최근의 반응 결과들을 살펴보고자 한다. AbstractThe dihydroxylation reaction of allylic amines is a facile and useful synthetic method to obtain amino diol structures that are widely found in lots of biologically important natural products. This review will focus on the recent methods of both substrate-controlled and ligand-controlled dihydroxylation reactions of acyclic allylic amines. In addition, several applications of the diastereoselective dihydroxylation methods to asymmetric syntheses of natural products are presented. Figure 1. Dihydroxylation reactions of chiral allylic amines for natural product synthesis. † Corresponding

Stereoselective Synthesis of Novel Bestatin Analogs

“…The initial nitro-alcohols 6 resulted from the nitro-aldol reaction between 4 and PhSO2CH2NO2 were dehydrated in-situ to result in the phenylsulfonylnitroolefin intermediates 7, which underwent the intramolecular conjugate addition to yield the cyclized adducts 5. The excellent stereoselectivity (>20:1) for trans-oxazolidines 5 could be rationalized by the favored H-eclipsed conformation of 7 [27][28]. The slower reactivity by the isopropyl analog 4b (R = i-Pr) might be also explained from the proposed mechanism (Scheme 3).…”

β‐Amino Propargylic Fluorides through Stereoselective Electrophilic Fluorodesilylation of 4‐Amino‐1‐allenylsilanes

“…The results obtained with 1,4‐ syn ‐4‐amino‐1‐allenylsilanes 3a–f were rationalized conveniently using the Houk‐like transition state model M1 wherein, without severe A 1,3 ‐strain, the deactivating NHAc substituent lies “inside” (Scheme ) . In this model, pathway (b) is much less favored than pathway (a) due to the steric interactions of electrophilic fluorine agent with both the R substituent and the Me 2 PhSi group.…”