Methyl .alpha.-phenylbutenoates

A methyl .alpha.-phenylbutenoate of the formula I ##STR9## where -- is a single or double bond and the index and the substituents have the following meanings:

• n is 0, 1, 2, 3 or 4, it being possible for the substituents R.sup.1 to be different if n is greater than 1;
• R.sup.1 is nitro, cyano, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl or C.sub.1 -C.sub.4 -alkoxy;
• R.sup.2 is hydrogen, nitro, cyano, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -alkylthio or C.sub.1 -C.sub.4 -alkoxycarbonyl;
• R.sup.3 is unsubstituted or substituted alkyl, alkenyl or alkynyl;
• an unsubstituted or substituted saturated or mono-or diunsaturated ring which, in addition to carbon atoms, optionally contains one to three of the following heteroatoms as ring members:
• oxygen, sulfur and nitrogen, or
• an unsubstituted or substituted mono-or binuclear aromatic radical which, in addition to carbon atoms optionally contains one to four nitrogen atoms or one or two nitrogen atoms and an oxygen or sulfur atom or an oxygen or sulfur atom as ring members.