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Malononitrile, reaction with dimedone

Subsequent reaction of the aldehyde with malononitrile gave the arylidenemalononitrile which upon reaction with dimedone afforded 281 (Scheme 92). [Pg.84]

The Knoevenagel reaction between benzaldehydes 22 and malononitrile or ethyl cyanoacetate 74 followed by condensation of the resulting ot,p-unsatu-rated nitriles 75 with dimedone (76) was performed in the presence of SiO2-(CH2)3-NEt2 (Scheme 3.22). ... [Pg.129]

When malononitrile was utilized, due to its higher acidity (pA 11.5) with respect to dimedone (pAa 12.0), the reaction could be carried out in a three-component manner by adding the reagents all at once the corresponding tetrahydrobenzo[ ]pyrans were isolated in 77-99% yield. [Pg.130]

The addition of water (see Section II,B) and other nucleophiles across the 3,4-double bond of quinazoline is well established. More recently other nucleophiles, such as dimedone, have given isolable 3,4-adducts. ° Similarly, malononitrile and other compounds with active methylene groups added across the 3,4-double bond of quinazoline, but in this case the reaction proceeded further with ring opening and formation of 2-amino-3-cyano-quinoline. The dimedone adduct was also made to react further in the presence of alkali to form the acridone 38. ... [Pg.23]

General procedure for the synthesis of 2-anuno-4-phenyl-3-cyano-7,7-dimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline (7). A mixture of aldehyde (1 2 mmol), dimedone (2 2 mmol), malononitrile or ethyl cyanoacetate (6 2 mmol), and ammonium acetate (4 3 mmol) was mixed thoroughly in a mortar with pestle followed by grinding till the completion of reaction as indicated by TLC (15-25 min). The resultant material was washed with water to remove any unreacted ammonium acetate and was air-dried to furnish the crude product. The pure product (7) was obtained by recrystaUization from ethyl alcohol. [Pg.100]


See other pages where Malononitrile, reaction with dimedone is mentioned: [Pg.175]    [Pg.47]    [Pg.82]    [Pg.83]    [Pg.502]    [Pg.502]    [Pg.481]    [Pg.190]   


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2- dimedone, reaction with

2- malononitrile, reaction

Dimedone—

Malononitrile

Malononitriles

Malononitriles reactions

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