Nickel-Catalyzed Hydrogenolysis and Conjugate Addition of 2-(Hydroxymethyl)pyridines via Organozinc Intermediates
作者:Luke E. Hanna、Michael R. Harris、Kenji Domon、Elizabeth R. Jarvo
DOI:10.1021/acs.orglett.7b03049
日期:2017.12.1
proposed to proceed through secondary benzylzinc reagents. Quenching with deuteromethanol provides straightforward incorporation of a deuterium label in the benzylic position. Intramolecular conjugateadditions with α,β-unsaturated esters are also demonstrated and support the intermediacy of a benzylzinc complex.
Iridium-Catalyzed Asymmetric Borylation of Unactivated Methylene C(sp<sup>3</sup>)–H Bonds
作者:Ronald L. Reyes、Tomohiro Iwai、Satoshi Maeda、Masaya Sawamura
DOI:10.1021/jacs.9b01952
日期:2019.5.1
Herein, we show the highly enantioselective borylation of unactivated methylene C(sp3)-Hbonds in 2-alkylpyridines and 2-alkyl-1,3-azole derivatives using an iridium-BINOL-based chiral monophosphite catalyst system. Quantum chemical calculations using the artificial force induced reaction (AFIR) method suggested that a monophosphite-Ir-tris(boryl) complex generates a narrow chiral reaction pocket where
Synthesis and Structure−Activity Relationships of Conformationally Constrained Histamine H<sub>3</sub> Receptor Agonists
作者:Ruengwit Kitbunnadaj、Obbe P. Zuiderveld、Iwan J. P. De Esch、Roeland C. Vollinga、Remko Bakker、Martin Lutz、Anthony L. Spek、Emile Cavoy、Marie-France Deltent、Wiro M. P. B. Menge、Henk Timmerman、Rob Leurs
DOI:10.1021/jm030905y
日期:2003.12.1
Immepip, a conformationally constrained analogue of the histamine congener imbutamine, shows high affinity and functional activity on the human H-3 receptor. Using histamine and its homologues as prototypes, other rigid analogues containing either a piperidine or pyrrolidine ring in the side chain were synthesized and tested for their activities at the human H-3 receptor and the closely related H-4 receptor. In the series of piperidine containing analogues, immepip was found to be the most potent H-3 receptor agonist, whereas its propylene analogue 13a was identified as a high-affinity neutral antagonist for the human H-3 receptor. Moreover, replacement of the piperidine ring of immepip by a pyrrolidine ring led to a pair of enantiomers that show a distinct stereoselectivity at the human H-3 and H-4 receptor.
Leitner, Michael B.; Kreher, Thomas; Sonnenschein, Helmut, Journal of the Chemical Society. Perkin Transactions 2 (2001), 1997, # 2, p. 377 - 381
作者:Leitner, Michael B.、Kreher, Thomas、Sonnenschein, Helmut、Costisella, Burkhard、Springer, Juergen