Mild Regiospecific Synthesis of 1-Alkoxy-isochromenes Catalyzed by Well-Defined [Silver(I)(Pyridine-Containing Ligand)] Complexes
摘要:
The synthesis of 3-substituted-1-alkoxyisochromenes starting from 2-alkynylbenzaldehydes and different alcohols is reported. The reaction is catalyzed by a silver(1) complex with an original macrocyclic pyridine-containing ligand. The approach is characterized by absolute regioselectivity, mild reaction conditions, good to excellent reaction yields, cleanness of the reaction, and reduced purification steps. The reaction mechanism was investigated by in-depth H-1 NMR experiments and an aimed "trapping" experiment.
The synthesis of 3-substituted-1-alkoxyisochromenes starting from 2-alkynylbenzaldehydes and different alcohols is reported. The reaction is catalyzed by a silver(1) complex with an original macrocyclic pyridine-containing ligand. The approach is characterized by absolute regioselectivity, mild reaction conditions, good to excellent reaction yields, cleanness of the reaction, and reduced purification steps. The reaction mechanism was investigated by in-depth H-1 NMR experiments and an aimed "trapping" experiment.
Mild Intermolecular Synthesis of a Cyclopropane‐Containing Tricyclic Skeleton: Unusual Reactivity of Isobenzopyryliums
作者:Shuxuan Liu、Hui Qian、Tianyu Zhang、Hongling Xie、Zhengyu Han、Wengang Guo、Hai Huang、Jianwei Sun
DOI:10.1002/anie.202108258
日期:2021.9.20
problems. Instead, the key cyclopropane ring was formed between the well-positioned nucleophile and electrophile in the adduct from the regioselective [4+2] cycloaddition. Thus, this unusual process also represents a new reactivity of the versatile isobenzopyryliums. The choice of a Brønsted acid catalyst with proper acidity is crucial to the high efficiency and selectivity for this multiple bond-forming