Ring Opening of Donor-Acceptor Cyclopropanes with the Azide Ion: A Tool for Construction of N-Heterocycles
作者:Konstantin L. Ivanov、Elena V. Villemson、Ekaterina M. Budynina、Olga A. Ivanova、Igor V. Trushkov、Mikhail Ya. Melnikov
DOI:10.1002/chem.201405551
日期:2015.3.23
general method for ringopening of various donor–acceptor cyclopropanes with the azide ion through an SN2‐like reaction has been developed. This highly regioselective and stereospecific process proceeds through nucleophilic attack on the more‐substituted C2 atom of a cyclopropane with complete inversion of configuration at this center. Results of DFT calculations support the SN2 mechanism and demonstrate
已经开发出一种通用的方法,可通过类似S N 2的反应,将叠氮离子与各种供体-受体环丙烷开环。这种高度区域选择性和立体选择性的过程是通过亲核攻击环丙烷的更取代的C2原子进行的,该中心的构型完全反转。DFT计算结果支持S N2机理,证明环丙烷的相对实验反应性与计算出的能垒之间具有良好的定性相关性。该反应为多种多官能叠氮化物提供了一种简单的方法,产率高达91%。这些叠氮化物具有很高的合成效用,并参与了面向多样性的合成,这是通过已开发的将其转变为五元,六元和七元N杂环以及复杂的环状化合物的多径策略证明的。包括天然产物和药物,如(-)-尼古丁和阿托伐他汀。
Tertiary and Quaternary Carbon Formation via Gallium-Catalyzed Nucleophilic Addition of Organoboronates to Cyclopropanes
作者:Truong N. Nguyen、Jeremy A. May
DOI:10.1021/acs.orglett.7b03349
日期:2018.1.5
via homoconjugate addition of organoboron nucleophiles to diester- and ketone-functionalized cyclopropanes. Electron donor group cyclopropane substituents were not needed, allowing electron-deficient aryl, alkenyl, alkyl, and hydrogen-substituted cyclopropanes to be used. The catalytic conditions were compatible with alkenyl, alkynyl, and arylnucleophiles, including ortho-substituted aromatics, to
Scope and Mechanism for Lewis Acid-Catalyzed Cycloadditions of Aldehydes and Donor−Acceptor Cyclopropanes: Evidence for a Stereospecific Intimate Ion Pair Pathway
作者:Patrick D. Pohlhaus、Shanina D. Sanders、Andrew T. Parsons、Wei Li、Jeffrey S. Johnson
DOI:10.1021/ja8015928
日期:2008.7.1
In this work, the one-step diastereoselective synthesis of cis-2,5-disubstituted tetrahydrofuransviaLewis acid catalyzed [3 + 2] cycloadditions of donor-acceptor (D-A) cyclopropanes and aldehydes is described. The scope and limitations with respect to both reaction partners are provided. A detailed examination of the mechanism has been performed, including stereochemical analysis and electronic profiling
Lewis Acid Catalyzed Ring-Opening 1,3-Aminothiolation of Donor–Acceptor Cyclopropanes Using Sulfenamides
作者:Avishek Guin、Thukaram Rathod、Rahul N. Gaykar、Tony Roy、Akkattu T. Biju
DOI:10.1021/acs.orglett.0c00483
日期:2020.3.20
donor-acceptor (D-A) cyclopropanes using sulfenamides has been demonstrated. The insertion of the C-C σ-bond of D-A cyclopropanes into the S-N σ-bond of sulfenamides allows the synthesis of diverse γ-aminated α-thiolated malonic diesters in moderate to good yields (up to 87%) with good functional group compatibility. The stereospecificity of the reaction was demonstrated using enantiomericallypure D-A cyclopropane
Lewis Acid Catalyzed Nucleophilic Ring Opening and 1,3-Bisfunctionalization of Donor–Acceptor Cyclopropanes with Hydroperoxides: Access to Highly Functionalized Peroxy/(α-Heteroatom Substituted)Peroxy Compounds
作者:Kuldeep Singh、Tishyasoumya Bera、Vandana Jaiswal、Subrata Biswas、Biplab Mondal、Dinabandhu Das、Jaideep Saha
DOI:10.1021/acs.joc.8b02561
日期:2019.1.18
catalyzed ring opening reaction of Donor–Acceptor (D–A) cyclopropanes with alkyl hydroperoxides is reported to furnish various peroxycarbonyls and 1,3-haloperoxygenated compounds in good to excellent yields. This method adds another instance to scarcely reported noncyclilizing 1,3-bisfunctionalization of D–A cyclopropanes with two different functional groups and relies on the dual role of peroxide as nucleophile