摘要 |
A process suitable for safely mass-producing, through a short step, cyclic compounds useful in medicines, agricultural chemicals, foods, cosmetics, and chemical products or as intermediates therefor. The process, which is for producing a compound represented by the formula: <CHEM> äwherein Z represents an electron-attracting group; W represents optionally substituted ethylene or optionally substituted vinylene; R<3> represents hydrogen or an optionally substituted hydrocarbon group; and X represents a divalent group Äprovided that when W represents optionally substituted vinylene, then -X-CH2 -Z is not -X<1> -X<2> -CH2 -Z (wherein X<1> represents sulfur or optionally substituted nitrogen and X<2> represents optionally substituted ethylene)Üü or a salt thereof, is characterized by subjecting a compound represented by the formula (II) or a salt thereof: <CHEM> (wherein the symbols have the same meanings as the above) to a ring closure reaction in a solvent containing a carbonic diester. |