To obtain a cyclic oligocarbonate useful as a precursor in the production of polycarbonates and polyesters by reacting bischlorocarbonic ester of a specified bisphenol with isatinbisphenol.
A bischlorocarbonic ester of formula I (wherein Ar is a 6-30C difunctional aromatic residue of a dihydroxy compound; and (w) is 1-4) is mixed with an isatinbisphenol of formula II (wherein R1 to R4 are each H, a halogen or a 1-4C alkyl) and optionally a dehydroxy compound of the formula: HO-Ar- OH in such amounts that the molar ratio of the dihydroxy compound to the isatinbisphenol is 99:1 to 85:15, and the obtained mixture is reacted at 30-100°C for 10-60min in the presence of a catalyst such as triethylamine or N- methylpiperidine in a two-phase mixture comprising an organic solvent such as methylene chloride or cholorobenzene and water to obtain a mixture containing at least two compounds selected among compounds of formulas III to VI (wherein (x), (y) and (z) are each 0-20).
PRIDDY DUANE B JR
CHEN YUN
PIELARTZIK HARALD
KUMPF ROBERT-JOSEPH
