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Mechanochemical Knoevenagel condensation investigated in situ.

ABSTRACT: The mechanochemical Knoevenagel condensation of malononitrile with p-nitrobenzaldehyde was studied in situ using a tandem approach. X-ray diffraction and Raman spectroscopy were combined to yield time-resolved information on the milling process. Under solvent-free conditions, the reaction leads to a quantitative conversion to p-nitrobenzylidenemalononitrile within 50 minutes. The in situ data indicate that the process is fast and proceeds under a direct conversion. After stopping the milling process, the reaction continues until complete conversion. The continuous and the stopped milling process both result in crystalline products suitable for single crystal X-ray diffraction.

SUBMITTER: Haferkamp S

PROVIDER: S-EPMC5629385 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Mechanochemical Knoevenagel condensation investigated in situ.

Haferkamp Sebastian S Fischer Franziska F Kraus Werner W Emmerling Franziska F

Beilstein journal of organic chemistry 20170926

The mechanochemical Knoevenagel condensation of malononitrile with <i>p</i>-nitrobenzaldehyde was studied in situ using a tandem approach. X-ray diffraction and Raman spectroscopy were combined to yield time-resolved information on the milling process. Under solvent-free conditions, the reaction leads to a quantitative conversion to <i>p</i>-nitrobenzylidenemalononitrile within 50 minutes. The in situ data indicate that the process is fast and proceeds under a direct conversion. After stopping t ...[more]

PMID: 29062421

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