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。
Rhodium(<scp>iii</scp>)-catalyzed cascade C–H functionalization/annulation of sulfoximines with iodonium ylides for the synthesis of cyclohexanone-1,2-benzothiazines
作者:Lu Chen、Zhichao Wang、Yangyang Wang、Liqiang Hao、Xiaobo Xu、Gaorong Wu、Yafei Ji
DOI:10.1039/d1ob02110a
日期:——
A highly efficient Rh(III)-catalyzed cascade C–H activation/annulation of sulfoximines with iodonium ylides under metal-oxidant-free conditions has been reported. The fused cyclohexanone-1,2-benzothiazine scaffold is readily achieved with a one-pot process in this reaction. This protocol exhibits good functional group tolerance and moderate to excellent yields. Additionally, the olefination of the
已经报道了在无金属氧化剂的条件下,一种高效的 Rh( III ) 催化的级联 C-H 活化/环化亚砜亚胺与碘鎓叶立德。在该反应中,通过一锅法很容易实现融合的 cyclohexanone-1,2-benzothiazine 支架。该协议表现出良好的官能团耐受性和中等至优异的产量。此外,目标产物的烯烃化说明了该策略的前景广阔。
Rh(<scp>iii</scp>)-Catalyzed C(sp<sup>2</sup>)–H functionalization/cyclization cascade of <i>N</i>-carboxamide indole and iodonium reagents for access to indoloquinazolinone derivatives
作者:Zhi-Peng Han、Meng-Meng Xu、Rui-Ying Zhang、Xiao-Ping Xu、Shun-Jun Ji
DOI:10.1039/d1gc01820e
日期:——
A rhodium-catalyzed synthesis of indoloquinazolinone from a readily available hypervalent iodonium reagent and N-carboxamide indole was developed. The protocol features broad functional group tolerance, mild conditions, and excellent yields. The target products were obtained simply by filtration, without tedious column chromatography. Notably, the noble metal catalyst system can be recycled effectively