Efficient Nazarov Cyclizations of 2-Alkoxy-1,4-pentadien-3-ones
摘要:
[GRAPHICS]Expeditious and high-yielding Nazarov cyclizations of 2-alkoxy-1,4-pentadien-3-ones are described. An example of a catalytic asymmetric Nazarov cyclization is presented.
Efficient Nazarov Cyclizations of 2-Alkoxy-1,4-pentadien-3-ones
摘要:
[GRAPHICS]Expeditious and high-yielding Nazarov cyclizations of 2-alkoxy-1,4-pentadien-3-ones are described. An example of a catalytic asymmetric Nazarov cyclization is presented.
An efficient metal-free catalytic protocol for the electrocyclization of alpha-alkoxydienones to cyclopentenones (Nazarov reaction) in near to quantitative yields is described. The key parameters are the use of inexpensive 4-toluenesulfonic acid in 5 mol % at room temperature in acetonitrile or under solvent-free conditions. The versatility of the transformation is demonstrated with unpolarized dienones with good regioselectivities and excellent yields. (c) 2008 Elsevier Ltd. All rights reserved.
Efficient Nazarov Cyclizations of 2-Alkoxy-1,4-pentadien-3-ones
作者:Guangxin Liang、Stefan N. Gradl、Dirk Trauner
DOI:10.1021/ol036019z
日期:2003.12.1
[GRAPHICS]Expeditious and high-yielding Nazarov cyclizations of 2-alkoxy-1,4-pentadien-3-ones are described. An example of a catalytic asymmetric Nazarov cyclization is presented.
Nazarov-type Reactions in Water
作者:Masaya Kokubo、Shū Kobayashi
DOI:10.1002/asia.200800461
日期:2009.4.6
AbstractDifferent in water! We have developed Nazarov‐type reactions in water. Different reaction courses compared with those in organic solvents are observed in water. In the presence of a scandium based, surfactant‐type catalyst, water‐trapping products are obtained exclusively. The results presented are unprecedented and provide a valuable extension to information available regarding organic reactions in water.magnified image