We herein report an unprecedented photoinduced cyclization/defluorination domino process of N-allylbromodifluoroacetamide with cyclic secondaryamines. Consequently, a wide array of valuable 3-fluoro-1,5-dihydro-2H-pyrrol-2-ones were facilely prepared from readily available starting materials under mild conditions. Preliminary mechanistic investigations suggest that a radical chain propagation and
我们在此报告了N-烯丙基溴二氟乙酰胺与环状仲胺的前所未有的光致环化/脱氟多米诺骨牌过程。因此,在温和的条件下,从容易获得的起始材料中轻松制备了一系列有价值的 3-fluoro-1,5-dihydro-2 H -pyrrol-2-ones。初步的机理研究表明,自由基链增长和胺促进的脱氟途径可能参与了这种转变。
Construction of Boronated
<i>γ</i>
‐Lactams via Palladium‐Catalyzed Intramolecular Boryldifluoroalkylation of Alkenes
作者:Wu‐Jie Lin、Yu‐Zhao Wang、Jian‐Yu Zou、Yi‐Chuan Zhao、Jin‐Lin Wang、Xue‐Yuan Liu
DOI:10.1002/adsc.202000786
日期:2020.11.18
for the preparation of boronated γ‐lactams viapalladium‐catalyzed boryldifluoroalkylation of alkenes with α‐bromodifluoroacetamides was developed. This method exhibits good functional group tolerance. Various boronated products were obtained in moderate to good yields for 1 h. Mechanistic studies indicated that this reaction may involve an intramolecular radical cascade cyclization process.
Visible Light-Promoted Radical Relay Cyclization/C–C Bond Formation of <i>N</i>-Allylbromodifluoroacetamides with Quinoxalin-2(1<i>H</i>)-ones
作者:Zhi-Peng Ye、Fang Liu、Xin-Yu Duan、Jie Gao、Jian-Ping Guan、Jun-An Xiao、Hao-Yue Xiang、Kai Chen、Hua Yang
DOI:10.1021/acs.joc.1c02285
日期:2021.12.3
A visible light-promoted radical relay of N-allylbromodifluoroacetamide with quinoxalin-2(1H)-ones was developed in which 5-exo-trig cyclization and C–C bond formation were involved. This protocol was performed under mild conditions to facilely offer a variety of hybrid molecules bearing both quinoxalin-2(1H)-one and 3,3-difluoro-γ-lactam motifs. These prepared novel skeletons would expand the accessible
A visible-light-induced tandem radical intramolecular cyclization/arylation of quinoxalin-2(1H)-ones with bromodifluoroacetamides is described. This protocol allows efficient access to a variety of valuable α,α-difluoro-γ-lactam-fused quinoxalin-2(1H)-ones in moderate to good yields under metal-free, mild and redox neutral reaction conditions. This strategy is tolerant of various functional groups
描述了 quinoxalin-2(1 H )-ones 与溴二氟乙酰胺的可见光诱导的串联自由基分子内环化/芳基化。该协议允许在无金属、温和和氧化还原中性反应条件下以中等至良好的产率有效访问各种有价值的α、α-二氟-γ-内酰胺-融合 quinoxalin-2(1 H )-ones。该策略对各种官能团和广泛的底物具有耐受性。机制实验表明 5 - exo -trig 环化和该转化中的激进过程的参与。
Stereodivergent atom-transfer radical cyclization by engineered cytochromes P450
作者:Qi Zhou、Michael Chin、Yue Fu、Peng Liu、Yang Yang
DOI:10.1126/science.abk1603
日期:2021.12.24
Naturallyoccurring enzymes can be a source of unnatural reactivity that can be molded by directed evolution to generate efficient biocatalysts with valuable activities. Owing to the lack of exploitable stereocontrol elements in synthetic systems, steering the absolute and relative stereochemistry of free-radical processes is notoriously difficult in asymmetric catalysis. Inspired by the innate redox