Karabasanagouda; Adhikari, Airody Vasudeva; Girisha, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2009, vol. 48, # 3, p. 430 - 437
Iron-Catalyzed Hydroboration of Vinylcyclopropanes
作者:Chenhui Chen、Xuzhong Shen、Jianhui Chen、Xin Hong、Zhan Lu
DOI:10.1021/acs.orglett.7b02691
日期:2017.10.6
An iron-catalyzed hydroboration of vinylcyclopropane with HBpin is first reported for the preparation of valuable homoallylic organoboronic esters. The iron catalysts enable efficient and regioselective C–C cleavage of vinylcyclopropanes, stereoselectively delivering E-alkenes with good stereospecific selectivity at an allylic position. This protocol exhibits mild conditions with good functional group
A one-pot fluorination and organocatalytic Robinson annulation sequence has been developed for asymmetric synthesis of 6-fluoroyclohex-2-en-1-ones and 4,6-difluorocyclohex-2-en-1-ones. The reactions promoted by cinchona alkaloid amine afforded products bearing two or three stereocenters in good to excellent yields with up to 99% ee and 20:1 dr.
Enantioselective Conjugate Addition of Catalytically Generated Zinc Homoenolate
作者:Yoshiya Sekiguchi、Naohiko Yoshikai
DOI:10.1021/jacs.1c00869
日期:2021.3.31
derivatives with good to high enantioselectivities. The reaction has proved applicable to various 1-substituted cyclopropanols as well as chalcones and related enones. The chiral amino alcohol has proved to enable ligand-accelerated catalysis of the homoenolate generation and its conjugate addition. Positive nonlinear effects and lower reactivity of a racemic catalyst have been observed, which can be
我们在此报告了通过环丙醇开环催化生成的均烯酸锌与 α,β-不饱和酮的对映选择性共轭加成反应。反应由 Et 2生成的氨基醇锌催化剂促进Zn 和手性 β-氨基醇生成 1,6-二酮,加热后发生分子内醇醛缩合反应,生成具有良好至高对映选择性的高度取代的环戊烯衍生物。该反应已证明适用于各种 1-取代环丙醇以及查耳酮和相关烯酮。手性氨基醇已被证明能够实现同烯醇化物生成及其共轭加成的配体加速催化。已经观察到外消旋催化剂的正非线性效应和较低的反应性,这可归因于稳定且非活性的异手性氨基醇锌二聚体。
Substituent effects in pyridyl-functionalized pyrylium salts, pyridines and λ<sup>3</sup>,σ<sup>2</sup>-phosphinines: a fundamental and systematic study
作者:Antonia Loibl、Wiebke Oschmann、Maria Vogler、Evgeny A. Pidko、Manuela Weber、Jelena Wiecko、Christian Müller
DOI:10.1039/c8dt01441h
日期:——
derivatives for comparison reasons. Reaction of the chelating ligands with [W(CO)6] in THF afforded the corresponding [(P^N)W(CO)4] and [(N^N)W(CO)4] complexes. A crystallographic characterization of selected coordinationcompounds revealed significant structural differences between the pyridyl-phosphinine- and the bipyridine-based compounds. Their characterization by means of IR-spectroscopy gave experimental