Enolate salts of 4-fluoro-2-hydroxymethylene-3-oxobutyrates of formula wherein R1 is C1-10 alkyl, R2 and R3 are independently hydrogen or fluorine, M is an alkali or alkaline earth metal, and n is 1 or 2, are prepared from enolate salts of the corresponding 4-fluoro-3-oxobutyrates and carbon monoxide. The apparatus includes a disc drive that determines whether a disc inserted therein can be recorded to; and a processor that obtains information from the disc drive as to whether the disc drive can record to the disc, and displays the information regarding the disc if the disc drive cannot record to the disc. In particular, the second scaling factor is estimated based on the lower frequency components of the synthesized speech and the coloring of the artificial signal is based on the linear predictive coding coefficients characteristic of the lower frequency of the input signal. Exterior covering, or siding, is attached to the exterior surface to surround a portion of the mount. The plurality of metal complexes are bound to each other via a polydentate ligand that substitutes partially the ligands of the two or more metal complexes, and have 2 to 1000 metal atoms.