Rhodium(II)-Catalyzed Reaction of Iodonium Ylides with Conjugated Compounds: Efficient Synthesis of Dihydrofurans, Oxazoles, and Dihydrooxepines
作者:Yong Lee、Sang Yoon、Youngwan Seo、Bong Kim
DOI:10.1055/s-2004-831257
日期:——
The rhodium(II)-catalyzed reaction of iodonium ylides with a variety of conjugated compounds has been examined. With α,β-unsaturatedesters and α,β-unsaturated ketones, dihydrofurans were produced in moderate yields. Reactions with acrylonitriles yield oxazoles and dihydrofurans in moderate yields, whereas reactions with 1,3-butadienes result in dihydrofurans and dihydrooxepines in good yields, respectively
已经检查了碘鎓叶立德与各种共轭化合物的铑 (II) 催化反应。使用 α,β-不饱和酯和 α,β-不饱和酮,以中等收率生产二氢呋喃。与丙烯腈反应以中等收率产生恶唑和二氢呋喃,而与 1,3-丁二烯反应分别以良好收率产生二氢呋喃和二氢氧杂环庚烷。形成这些产物的机理途径已根据环丙烷中间体或 1,3-偶极环加成机理进行了描述。
Iodonium Ylides as Carbene Precursors in Rh(III)-Catalyzed C–H Activation
作者:Yuqin Jiang、Pengfei Li、Jie Zhao、Bingxian Liu、Xingwei Li
DOI:10.1021/acs.orglett.0c02618
日期:2020.10.2
The rhodium(III)-catalyzed coupling of C–H substrates with iodonium ylides has been realized for the efficientsynthesis of diverse cyclic skeletons, where the iodonium ylides have been identified as efficient and outstanding carbene precursors. The reaction systems are applicable to both sp2 and sp3 C–H substrates under mild and redox-neutral conditions. The catalyst loading can be as low as 0.5 mol
Rhodium(III)-Catalyzed Regioselective Decarboxylative Cyclization for the Synthesis of 4<i>H</i>-Furo[3,2-<i>c</i>]chromen-4-one Derivatives
作者:Dandan Zha、Hongji Li、Shiqing Li、Lei Wang
DOI:10.1002/adsc.201600974
日期:2017.2.2
This contribution describes a regioselective cyclization of hypervalent iodine reagents (HIR) with propiolic acids in the presence of a rhodium catalyst. The mild decarboxylation can tolerate a wide range of groups and generates 4H‐furo[3,2‐c]chromen‐4‐one derivatives in good isolated yields.
该贡献描述了在铑催化剂存在下用丙酸对高价碘试剂(HIR)的区域选择性环化。轻度的脱羧可以耐受广泛的基团,并以良好的分离产率生成4 H-呋喃[3,2 - c ] chromen-4-one衍生物。
4-Thio coumarins
申请人:——
公开号:US20040180950A1
公开(公告)日:2004-09-16
4-Thio substituted coumarin derivatives, 4,5-dithio substituted coumarin derivatives, and coumarin dimers are provided, as well as processes for their preparation. The invention also provides a method and composition for the treatment of hepatitis C virus (HCV) by adiministering 4-thio substituted coumarin derivatives, 4,5-dithio substituted coumarin derivatives, and coumarin dimers.
Rh(
<scp>III</scp>
)‐Catalyzed Diverse C—H Functionalization of Iminopyridinium Ylides
作者:Zhenzhen Dong、Pengfei Li、Xingwei Li、Bingxian Liu
DOI:10.1002/cjoc.202100203
日期:2021.9
Divergent synthesis of useful skeletons has been realized via rhodium(III)-catalyzed C—H activation of iminopyridinium ylides and coupling with various unsaturated coupling reagents. Isocoumarins and isoquinolones were obtained via cleavage of the C—N or N—N bond in the ylidic directing group, while fluorinated alkenes were delivered with the directing group intact. The reactions occurred with wide