Palladacycle-Catalyzed Reaction of Bicyclic Alkenes with Terminal Ynones: Regiospecific Synthesis of Polysubstituted Furans
摘要:
A new synthetic strategy to access polysubstituted furans regiospecifically has been developed using simple bicyclic alkenes and terminal ynones as starting materials with palladacycles as unique active catalysts. A rational mechanism has also been proposed. This reaction features mild reaction conditions, easily available starting materials and palladacycle catalysts, a wide substrate scope, and high regiospecificity.
Styrene as 4π-Component in Zn(II)-Catalyzed Intermolecular Diels–Alder/Ene Tandem Reaction
作者:Min Zheng、Feng Wu、Kai Chen、Shifa Zhu
DOI:10.1021/acs.orglett.6b01511
日期:2016.8.5
A mild Zn-catalyzed intermolecular Diels–Alder/ene tandemreaction with styrene as a 4π-component is reported. A variety of dihydronaphthalene products could be prepared in moderate to good yields. Moreover, a combination of DFT calculations and experiments was performed to further understand the mechanism of this unique tandemreaction.
Diversity-Oriented Synthesis Based on the DPPP-Catalyzed Mixed Double-Michael Reactions of Electron-Deficient Acetylenes and β-Amino Alcohols
作者:Yi Chiao Fan、Ohyun Kwon
DOI:10.3390/molecules16053802
日期:——
opane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes. These reactions are very suitable for the diversity-oriented parallel syntheses of oxizolidines because: (i) they are performed under mild metal-free conditions and (ii) the products are isolated without complicated work-up. To demonstrate the applicability of mixed double-Michael reactions
A straightforward indole synthesis via annulation of C-nitrosoaromatics with conjugated terminal alkynones was realised achieving a simple, highly regioselective, atom- and step economical access to 3-aroylindoles in moderate to good yields. Further functionalizations of indole scaffolds were investigated and an easy way to JWH-018, a synthetic cannabinoid, was achieved.
Enantioselective [3 + 2] annulation of 4-isothiocyanato pyrazolones and alkynyl ketones under organocatalysis
作者:Wenyao Wang、Shiqiang Wei、Xiaoze Bao、Shah Nawaz、Jingping Qu、Baomin Wang
DOI:10.1039/d0ob02423f
日期:——
4-isothiocyanato pyrazolones with alkynylketones in the presence of an organic catalyst derived from a cinchona alkaloid under mild conditions is realized. This protocol provides unprecedented expeditious access to a wide range of optically active spiro[pyrroline–pyrazolones] with various electronic properties in high yields with good to excellent enantioselectivities.
Substituted Pyrrololactams via Ring Expansion of Spiro-2<i>H</i>-pyrroles from Intermolecular Alkyne–Isocyanide Click Reactions
作者:Jimil George、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acs.orglett.6b03786
日期:2017.2.3
The facile synthesis of 6- to 8-membered pyrrololactams has been developed using a ringexpansion of spiro-2H-pyrroles, the products of intermolecular alkyne–isocyanide click reactions. The key to successful ringexpansion of spiro-2H-pyrroles to pyrrololactams is the enforced orbital overlap between the internal alkene and the amide carbonyl group through the conformationally locked bicyclic structures