(2E)-4-hydroxyalk-2-enals and 2-substituted furans as products of reactions of (2E)-4,4-dimethoxybut-2-enal with Grignard compounds
摘要:
Methods have been developed for the synthesis of (2E)-1,1-dimethoxyalk-2-en-4-ols and (2E)-4-hydroxyalk-2-enals by reaction of (2E)-4,4-dimethoxybut-2-enals and Grignard compounds. Thermal isomerization of (2E)-4-hydroxyalk-2-enals gave the corresponding 2-alkylfurans.
One-Pot Transformation of Simple Furans into Octahydroindole Scaffolds
作者:Dimitris Kalaitzakis、Myron Triantafyllakis、Georgios I. Ioannou、Georgios Vassilikogiannakis
DOI:10.1002/anie.201700620
日期:2017.3.27
A highly efficient and general singlet‐oxygen‐initiated one‐pot transformation of readily accessible furans into octahydroindolescaffolds has been developed.
已经开发了一种高效且通用的单线态氧引发的单锅法,将易得的呋喃转化为八氢吲哚支架。
The Power of Triplet and Singlet Oxygen in Synthesis: 2-Oxindoles, 3-Hydroxy-2-oxindoles, and Isatins from Furans
A straightforward synthesis of substituted 2-oxindoles, 3-hydroxy-2-oxindoles, and isatins has been developed. Easily accessible furans were transformed into tetrahydropyranopyrrolones by a singlet oxygen initiated cascade reaction sequence. An acid-catalyzedrearrangement, followed by aromatization, gave access to a variety of 2-oxindole motifs, which were oxidized to 3-hydroxy-2-oxindoles or isatins
Leveraging the Micellar Effect: Gold-Catalyzed Dehydrative Cyclizations in Water at Room Temperature
作者:Stefan R. K. Minkler、Nicholas A. Isley、Daniel J. Lippincott、Norbert Krause、Bruce H. Lipshutz
DOI:10.1021/ol403402h
日期:2014.2.7
The first examples of gold-catalyzed cyclizations of diols and triols to the corresponding hetero- or spirocycles in an aqueous medium are presented. These reactions take place within nanomicelles, where the hydrophobic effect is operating, thereby driving the dehydrations, notwithstanding the surrounding water. By the addition of simple salts such as sodium chloride, reaction times and catalyst loadings
Addition of carbon nucleophiles to aldehyde tosylhydrazones of aromatic and heteroaromaticcompounds is reported. New observations have been made wherein alkylative reduction is observed in some cases whereas alkylative fragmentation is noticed in others. These findings are exploited in the synthesis of the useful alkaloid piperine and its analogs.
Nickel Complex Catalyzed Efficient Activation of sp3 and sp2 C–H Bonds for Alkylation and Arylation of Oxygen Containing Heterocyclic Molecules
作者:Yashraj Gartia、Punnamchandar Ramidi、Darin E. Jones、Sharon Pulla、Anindya Ghosh
DOI:10.1007/s10562-013-1170-8
日期:2014.3
A nickel(II) complex (1) of N,N′-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamido (L) ligand was examined for catalytic coupling of Grignardreagents with the C–H bond of oxygen containing heterocyclic compounds such as tetrahydrofuran and furan. The nickel(II) complex showed excellent activity in catalyzing C–H activation and further coupling with various Grignardreagents. The effective activation