Redox-Neutral Synthesis of β-Amino Aldehydes from Imines by an Alkynylation/Hydration Sequence
摘要:
N-Protected beta-amino aldehydes have been prepared starting from imines through a sequence involving a Zn-mediated direct alkynylation followed by a Ru-catalyzed anti-Markovnikov alkyne hydration. The rate and the efficiency of the latter reaction are enhanced by the use of microwave irradiation. The possibility to carry out a one-pot Ru-catalyzed hydration/oxidation process from a terminal alkyne to a carboxylic acid was demonstrated, which provided direct access to a N-protected beta-amino acid from the corresponding terminal alkyne.
The Marriage of Organocatalysis with Metal Catalysis: Access to Multisubstituted Chiral 2,5-Dihydropyrroles by Cascade Iminium/Enamine-Metal Cooperative Catalysis
作者:Wangsheng Sun、Gongming Zhu、Liang Hong、Rui Wang
DOI:10.1002/chem.201103083
日期:2011.12.9
Organocatalyst and metal cooperate: The integration of iminiumcatalysis and enamine–metalcooperativecatalysis into a single process facilitates the rapid and controlled production of valuable chiral pyrrolines in excellent diastereo‐ and enantioselectivities (see scheme).
Gold(I)-Catalyzed Tandem Reaction of<i>γ</i>-Amino-Substituted Propargylic Esters to Pyrrolines and its Application in the Formal Synthesis of (±)-Aphanorphine
作者:Zhengshen Wang、Huaiji Zheng、Juan Yang、Xingang Xie、Xuegong She
DOI:10.1002/adsc.201401161
日期:2015.6.15
effective synthesis of structurally diverse pyrroline derivatives has been accomplished by a gold(I)‐catalyzed tandem 1,3‐acyloxy rearrangement/intramolecular azacylization reaction of γ‐amino‐substituted propargylic esters in good to excellent chemical yields (52–98%). The reaction proceeds under extremely mild conditions and has also demonstrated its potential in a concise formal synthesis of (±)‐aphanorphine
Tandem Reaction of Allenoate Formation and Cyclization: Divergent Synthesis of Four- to Six-Membered Heterocycles
作者:Danqing Ji、Kai Liu、Jiangtao Sun
DOI:10.1021/acs.orglett.8b03435
日期:2018.12.7
Tandem reactions of copper-catalyzed cross-coupling of N-substituted prop-2-yn-1-amines with diazoacetates and subsequent cyclization have been developed to prepare several types of four- to six-memberedheterocycles. Copper-catalyzed allenoate formation has been proven as the key step for the diverse annulations. Importantly, on the basis of the choice of different N-protecting groups of the alkyne substrates
Facile access to highly functionalized hydroisoquinoline derivatives<i>via</i>phosphine-catalyzed sequential [3+3]/[3+3] annulation
作者:Ning Li、Penghao Jia、You Huang
DOI:10.1039/c9cc05832j
日期:——
An unprecedented sequential [3+3]/[3+3] annulation of allenoates and dienes catalyzed by phosphine has been developed, which provides novel and facile access to highly functionalized hydroisoquinoline derivatives. The reaction features a wide reaction scope and mild reaction conditions. δ-sulfonamido-allenoates, acting as a five-atom unit, represent a new synthon in the reactions of allenoates.