Remote Oxidation of Aliphatic C–H Bonds in Nitrogen-Containing Molecules
摘要:
Nitrogen heterocycles are ubiquitous in natural products and pharmaceuticals. Herein, we disclose a nitrogen complexation strategy that employs a strong Bronsted acid (HBF4) or an azaphilic Lewis acid (BF3) to enable remote, non-directed C(sp(3))-H oxidations of tertiary, secondary, and primary amine- and pyridine-containing molecules with tunable iron catalysts. Imides resist oxidation and promote remote functionalization.
Multinuclear NMR Spectra, <sup>1</sup>H-T<sub>1</sub> Relaxation, Conformational Behavior, and Intramolecular H<sup>δ</sup><sup>-</sup>····<sup>δ</sup><sup>+</sup>H Contacts of N−Borane Cyclic Adducts in Solution
作者:Marisol Güizado-Rodríguez、Angelina Flores-Parra、Sonia A. Sánchez-Ruiz、Rafael Tapia-Benavides、Rosalinda Contreras、Vladimir I. Bakhmutov
DOI:10.1021/ic000890j
日期:2001.6.1
The VT H-1 NMR and H-1-NOESY spectra revealed "frozen" envelope conformations in solutions of 1 and 2 with the BR3 groups in equatorial positions. The H-1-T-1 relaxation measurements provided determinations of the intramolecular proton-hydride contacts in solutions of adducts 1 and 8.
Remote Oxidation of Aliphatic C–H Bonds in Nitrogen-Containing Molecules
作者:Jennifer M. Howell、Kaibo Feng、Joseph R. Clark、Louis J. Trzepkowski、M. Christina White
DOI:10.1021/jacs.5b10299
日期:2015.11.25
Nitrogen heterocycles are ubiquitous in natural products and pharmaceuticals. Herein, we disclose a nitrogen complexation strategy that employs a strong Bronsted acid (HBF4) or an azaphilic Lewis acid (BF3) to enable remote, non-directed C(sp(3))-H oxidations of tertiary, secondary, and primary amine- and pyridine-containing molecules with tunable iron catalysts. Imides resist oxidation and promote remote functionalization.
Allylic C–H amination cross-coupling furnishes tertiary amines by electrophilic metal catalysis
作者:Siraj Z. Ali、Brenna G. Budaitis、Devon F. A. Fontaine、Andria L. Pace、Jacob A. Garwin、M. Christina White
DOI:10.1126/science.abn8382
日期:2022.4.15
nondirected, electrophilic metal–catalyzed aminations tend to bind to and thereby inhibit metal catalysts. We reasoned that an autoregulatory mechanism coupling the release of amine nucleophiles with catalyst turnover could enable functionalization without inhibiting metal-mediated heterolytic carbon-hydrogen cleavage. Here, we report a palladium(II)-catalyzed allylic carbon-hydrogen amination cross-coupling
末端烯烃与仲胺的分子间交叉偶联形成复杂的叔胺(药物中的常见基序)仍然是化学合成的主要挑战。非定向亲电金属催化胺化中的碱性胺亲核试剂倾向于结合并抑制金属催化剂。我们推断,将胺亲核试剂的释放与催化剂周转相结合的自动调节机制可以在不抑制金属介导的异裂碳氢裂解的情况下实现功能化。在这里,我们使用这种策略报告了钯 (II) 催化的烯丙基碳-氢胺化交叉偶联,具有 48 个环状和无环仲胺(10 个药学相关核)和 34 个末端烯烃(带有亲电官能团),以提供 81 个叔烯丙基胺类,乙:Z)。