1. The reaction of 4(5)-methyl-2-imidazolinone with crotonyl chloride, chlorovinyl phenyl ketone or chlorovinyl n-amyl ketone in the presence of AlCl3 respectively, gives 4-methyl-5-crotonyl-, 4-methyl-5-phenylketovinyl- or 4-methyl-5-n-amylketovinyl-2-imidazolinone. 2. The regioselective bromination of 1,3-diacetyl-4-methyl-5-ethyl-2-imidazolinone with N-bromosuccinimide leads to 1,3-diacetyl-4-bromomethyl-5-ethyl-2-imidazolinone, which with sodioacetoacetic ester gives 1,3-diacetyl-4-ethyl-5-(2′-carbethoxy-3′-ketobutyl)-2-imidazolinone. 3. The reaction of methyl n-amyl ketone with ethyl formate and sodium in the presence of Me3SiCl and subsequent treatment of the formylation products with SOCl2 gives a mixture of chlorovinyl n-amyl ketone and 1-chloro-2-n-butyl-1-buten-3-one in a 7.5∶1 ratio.