Rh(III)-Catalyzed C–H Activation of Benzoylacetonitriles and Tandem Cyclization with Diazo Compounds to Substituted Benzo[<i>de</i>]chromenes
作者:Feifei Fang、Chunmei Zhang、Chaofan Zhou、Yazhou Li、Yu Zhou、Hong Liu
DOI:10.1021/acs.orglett.8b00103
日期:2018.4.6
Rh (III)-catalyzed C–H activation of benzoylacetonitriles in coupling with diazocompounds was developed to synthesize diversified substituted benzo[de]chromenes via a formal (4 + 2) cycloaddition with a diazocompound and subsequent tandem (4 + 2) cycloaddition with another diazocompound. Intriguingly, synthesis of substituted benzo[de]chromenes and their decarboxylation products could be realized
Rh(III)催化与重氮化合物偶合的苯甲酰基乙腈的C–H活化反应是通过与重氮化合物的正式(4 + 2)环加成反应和随后的串联(4 + 2)环加成反应,合成出多种取代的苯并[ de ]色烯。与另一种重氮化合物。有趣的是,通过控制反应条件,可以实现取代苯并[ de ]二甲基苯酮及其脱羧产物的合成。这些反应具有广泛的底物范围,中等至良好的产率,以及较高的区域选择性。
Rhodium-Catalyzed Cascade Oxidative Annulation Leading to Substituted Naphtho[1,8-<i>bc</i>]pyrans by Sequential Cleavage of C(sp<sup>2</sup>)–H/C(sp<sup>3</sup>)–H and C(sp<sup>2</sup>)–H/O–H Bonds
作者:Xing Tan、Bingxian Liu、Xiangyu Li、Bin Li、Shansheng Xu、Haibin Song、Baiquan Wang
DOI:10.1021/ja3075242
日期:2012.10.3
efficiently in the presence of a rhodium catalyst and a copper oxidant to give substituted naphtho[1,8-bc]pyrans by sequential cleavage of C(sp(2))-H/C(sp(3))-H and C(sp(2))-H/O-H bonds. These cascade reactions are highly regioselective with unsymmetrical alkynes. Experiments reveal that the first-step reaction proceeds by sequential cleavage of C(sp(2))-H/C(sp(3))-H bonds and annulation with alkynes
Variations on the Blaise Reaction: Synthesis of 3,5-Dioxopentanoates and 3-Amino-5-oxopent-3-enoates
作者:H. Rao、Nandurka Muthanna
DOI:10.1055/s-0035-1561662
日期:——
(α-cyano ketones) with ethyl bromoacetate. The reaction is a variation on the classical Blaise reaction, tuned to the synthesis of trifunctional compounds having 3,5-diketo ester or 3-enamino 5-keto ester functional groups. Our studies revealed that the Blaise reaction on the nitrile occurs in preference to the Reformatsky reaction on the neighboring ketone when the two functional groups are in a geminal
Selective Synthesis of β-Ketonitriles via Catalytic Carbopalladation of Dinitriles
作者:Ge Zeng、Jichao Liu、Yinlin Shao、Fangjun Zhang、Zhongyan Chen、Ningning Lv、Jiuxi Chen、Renhao Li
DOI:10.1021/acs.joc.0c02388
日期:2021.1.1
A practical, convenient, and highly selective method of synthesizing β-ketonitriles from the Pd-catalyzed addition of organoboron reagents to dinitriles has been developed. This method provides excellent functional-group tolerance, a broad scope of substrates, and the convenience of using commercially available substrates. The method is expected to show further utility in future synthetic procedures
An interesting σ-bond insertion/benzannulation reaction for the synthesis of polysubstituted naphthalene derivatives has been developed from readily accessible ketones, arynes, and alkynoates. This practical and transition-metal-free method provides a novel route to diverse naphthalenes through a substrate-controlled rearrangement reaction with the cleavage of C–C bonds.