Basic cesium-beta (Cs-beta) zeolite has been synthesized. It proved to be an effective catalyst in reactions of a number of alpha,beta-unsaturated carbonyl compounds with malononitrile. It is shown that the process is either the Michael or Knoevenagel reaction, or tandem transformations generally initiated by the Michael reaction, which depends on steric hindrance at the carboryl group and the beta-position of the carbon=carbon (C=C) double bond adjacent to the carbonyl group. (C) 2002 Elsevier Science B.V. All rights reserved.