Abstract
[Bmim]OH mediated new synthesis of 3-(1 H -Indol-3-Yl)Acrylonitrile derivatives 6 have been developed by the reaction of diethylphthalate 1 with ethyl cyanohydrazide 2 to form 3-(1, 4-dioxo-3, 4-dihydrophthalazin-(1H)-yl)-3-oxopropanenitrile 3. Then compound 3 reacted with indole-3-aldehyde 4 by Knoevenagel condensation to form compound (E)-2-(1, 4-dioxo-1, 2, 3, 4-tetrahydrophthalazine-2-carbonyl)-3-(1H-indol-3-yl)acrylonitriles 5 . Compound 5 under go alkylation with alkylating agents to form 6 with good yields. Compound 6 could also be synthesized by alkylation of 4 followed by condensation with 3.
Highlights
Ionic liquids as catalysts1 and /or media2 in reactions have been widely used in organic transformations due to their advantages such as good solvating ability, negligible vapor pressure, high polarity and ease of work-up. [Bmim]OH (1butyl-3-methylimidazolium hydroxide) is one such taskspecified ionic liquid which acts as reaction medium as well as a basic catalyst and has got various applications3 in the field of synthetic methodology development
We have developed the condensation of diethyl phthalate (1) (1 mmol), ethyl cyanoacetic acid hydrazide8 (2) (1 mmol) to from 3-(1,4-dioxo-3,4-dihydrophthalazin(1H)-yl)-3-oxopropanenitrile17 (3) in the presence of 1ethyl-3-methylimidazolium hydroxide solution [Bmim]OH (5 ml) at 80 °C for 15-20 min
Heterocycles containing the phthalazine moiety are of interest because they show some pharmacological and biological activities
Summary
Ionic liquids as catalysts1 and /or media2 in reactions have been widely used in organic transformations due to their advantages such as good solvating ability, negligible vapor pressure, high polarity and ease of work-up. [Bmim]OH (1butyl-3-methylimidazolium hydroxide) is one such taskspecified ionic liquid which acts as reaction medium as well as a basic catalyst and has got various applications3 in the field of synthetic methodology development. Compound 3 (1 mmol) was reacted with indole-3-aldehyde (4a) (1 mmol) in the presence of [Bmim]OH (5 ml) at 80 °C for 30-35 min to form 2-(1,4-dioxo-1,2,3,4-tetrahydrophthalazine-2-carbonyl)-3-(1H-indol-3-yl)acrylonitriles (5a) in 87 % yield on simple work-up of reaction mixture (TABLE 1, entry 1).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.