Abstract: An aliphatic diisocyanate compound is prepared in a high yield by reacting dimethyl carbonate with an aliphatic diamine in the presence of an alkali catalyst to produce a corresponding urethane compound; and, within 48 hours after the completion of the preparation of the urethane compound, thermally decomposing the urethane compound under a reduced pressure of 1 to 700 Torr in a high-boiling-point solvent.

Abstract: An aliphatic diisocyante compound is prepared in a high yield by reacting dimethyl carbonate with an aliphatic diamine in the presence of an alkali catalyst to produce a corresponding urethene compound; and, within 48 hours after the completion of the preparation of the urethane compound, thermally decomposing the urethane compound under a reduced pressure of 1 to 700 Torr in a high-boiling-point solvent.

Abstract: A carbonic acid ester is produced by reacting an alcohol with carbon monoxide and oxygen in the presence of a catalyst comprising a cupric salt of a weak acid and/or a cupric halide and an alkaline earth metal salt of a weak acid and/or an alkaline earth metal halide.

Abstract: A catalyst for hydrogenation, dehydrosilylation of ketones, or hydrosililation of dienes or acetylenes, comprising a complex represented the the formula:A.sup.+ [M.sub.2 H(C)).sub.10 ].sup.-wherein A.sup.+ represents an alkali metal cation, an ammonium cation, an iminium cation, or a phosphonium cation; and M represents a chromium atom, a molybdenum atom, or a tungsten atom; anda process for producing dehydrosilylation products of ketones or hydrosilylation products of dienes or acetylenes, which is characterized by using the complex as a catalyst.

Abstract: A process for preparing an .alpha.-phenylpropionic acid derivative wherein an .alpha.-phenylethyl alcohol derivative is reacted with carbon monoxide in the presence of a catalyst to give an .alpha.-phenylpropionic acid derivative, which comprises carrying out the reaction in either one of the following manners (I), (II) and (III):(I) effecting said reaction in the presence of a rhodium catalyst, as said catalyst, together with an iodine compound in such an amount as to give a Rh to I ratio on an atomic basis of 1:0.5 to 1:6; adjusting the concentration of water in the reaction mixture to a level of 2 mol/l or below; and employing a reaction temperature of 130.degree. C.

Abstract: A process for preparing an .alpha.-phenylpropionic acid derivative wherein an .alpha.-phenylethyl alcohol derivative is reacted with carbon monoxide in the presence of a catalyst to give an .alpha.-phenylpropionic acid derivative, which comprises carrying out the reaction in either one of the following manners (I), (II) and (III):(i) effecting said reaction in the presence of a rhodium catalyst, as said catalyst, together with an iodine compound in such an amount as to give a Rh to I ratio on an atomic basis of 1:0.5 to 1:6; adjusting the concentration of water in the reaction mixture to a level of 2 mol/l or below; and employing a reaction temperature of 130.degree. C.