The one-pot synthesis of malononitrile derivatives 4, 6, and 7 in moderate to high yields by the reaction of ylidenemalononitriles 3, prepared in situ from carbonyl compounds 1 and malononitrile 2 in the presence of ammonium acetate in aqueous solution at 50–60° C, with Et3B or RI 5/Et3B in a water–diethyl ether biphase medium under an atmosphere of room temperature is reported. The reaction of Et3B with adamantyl iodides 8 and 10 under ...