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The catalytic mechanism entails reversible formation of an imidoyl chloride (also known as the 'Vilsmeier reagent'): [27] [28] DMF penetrates most plastics and makes them swell. Because of this property DMF is suitable for solid phase peptide synthesis and as a component of paint strippers. DMF is used as a solvent to recover olefins such as 1 ...
Droplet formation using a flow focusing device. [17] Diagram of flow focusing droplet formation device commonly used in microfluidic devices. Liquid flowing in from the left is pinched off into droplets by an oil flowing in from the top and bottom. [10] Two stream reagent addition using a flow focusing approach with a planar chip format. [18]
The coupling of digital microfluidics (DMF) and Mass Spectrometry can largely be categorized into indirect off-line analysis, direct off-line analysis, and in-line analysis [17] and the main advantages of this coupling are decreased solvent and reagent use, as well as decreased analysis times. [105]
The first step of the Bouveault aldehyde synthesis is the formation of the Grignard reagent. Upon addition of a N , N -disubstituted formamide (such as dimethylformamide ) a hemiaminal is formed, which can easily be hydrolyzed into the desired aldehyde.
The major disadvantage with solids is that the water has to be accessible and easily brought into methanol solution. Many common substances, especially foods such as chocolate, release water slowly and with difficulty, requiring additional efforts to reliably bring the total water content into contact with the Karl Fischer reagents.
The Vilsmeier reagent is an organic compound with the formula [(CH 3) 2 NCHCl]Cl. It is a salt consisting of the N,N-dimethyliminium cation ([(CH 3) 2 N=CHCl] +) and chloride anion. Depending on the particular reaction, the anion can vary. In typical POCl 3-based reactions, the anion is PO 2 Cl 2 −.
This leads to what is known as the Glaser coupling reaction, which is an undesired formation of homocoupling products of acetylene derivatives upon oxidation. As a result, when running a Sonogashira reaction with a copper co-catalyst, it is necessary to run the reaction in an inert atmosphere to avoid the unwanted dimerization.
The reaction of a substituted amide with phosphorus oxychloride gives a substituted chloroiminium ion (2), also called the Vilsmeier reagent. The initial product is an iminium ion (4b), which is hydrolyzed to the corresponding ketone or aldehyde during workup. [7] The Vilsmeier–Haack reaction