Triphenyl phosphine(PPh3), an efficient and reusable catalyst, catalysed the synthesis of 2-amino-3-cyano-6-methyl-4-aryl-4H-pyran-5-ethylcarboxylate derivatives by one-pot condensation of aromatic aldehydes, malononitrile and ethyl acetoacetate in EtOH-H2O (1:1) at reflux conditions. The results show that ...

An efficient base catalysed approach to the synthesis of thiochromans/chromenes from allenylphosphonates (and an allenoate) and substrates having SH/OH and CHO groups at appropriate positions has been developed. Several azo-linked chromenes that are bright red pigments are also synthesized. This methodology involves the domino reactions of Michael addition and subsequent cyclisation by intramol...

nanoporous sodium montmorillonite clay (na+-mmt) was used as a support for the immobilization of 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate (na+-mmt-[pmim]hso4). this catalyst showed excellent catalytic activity for the preparation of 2-amino-3-cyano-5-oxo-5,6,7,8-tetrahydro-4h-benzopyrans via three-component reactions between aldehydes, dimedone and malononitrile. the proc...